Alesis Stereo Equalizer DEQ230 User Manual

Reference Manual  
 
Table Of Contents  
Introduction ..................................................................3  
Welcome!......................................................................................................3  
DEQ230 Key Features .................................................................... 4  
How to Use This Manual................................................................ 5  
Important Safety Instructions..................................7  
Important Safety Instructions (English)................................... 7  
Safety symbols used in this product.........................................................7  
Please follow these precautions when using this product: ...................7  
Instructions de Sécurité Importantes (French) ...................... 9  
Symboles utilisés dans ce produit.............................................................9  
Veuillez suivre ces précautions lors de l’utilisation de  
l’appareil: ......................................................................................................9  
Lesen Sie bitte die folgende Sicherheitshinweise  
(German) ........................................................................................... 11  
Sicherheit Symbole verwendet in diesem Produkt.................................11  
Folgen Sie bitte diesen Vorkehrungen, wenn dieses  
Produkt verwendet wird: ...........................................................................11  
CE Declaration Of Conformity..................................................... 13  
FCC Compliance Statement ......................................................... 13  
Chapter One: Quick Start Guide..............................15  
If you can't wait to get started..................................................................15  
Step 1: Hook it up to a mixer........................................................ 15  
Step 2: Try some equalization...................................................... 16  
Step 3: Store the Program............................................................. 16  
Chapter Two: Connections ........................................19  
Unpacking and Inspection............................................................ 19  
Installing in a Rack ........................................................................ 19  
Thermal Considerations in Rack Mounting ............................. 19  
AC Power Hookup........................................................................... 20  
To use the DEQ230 in another country:................................................20  
Connecting Inputs and Outputs.................................................. 21  
Connecting to the Channel or Main Inserts of a mixing  
console..........................................................................................................21  
Connecting to the inserts on an instrument amplifier..........................23  
Connecting to equipment with XLR inputs and outputs.....................23  
Connecting to equipment with S/PDIF inputs and  
outputs (DEQ230D only) ...........................................................................23  
About Audio Cables ........................................................................ 25  
Chapter Three: Basics of Equalization...................27  
What is equalization? ..................................................................... 27  
Description of the Controls .......................................................... 28  
Description of the Basic Modes ................................................... 29  
Basic operation: Program mode.................................................. 31  
Basic operation: Edit mode........................................................... 32  
 
1
Table Of Contents  
Basic operation: Store mode......................................................... 38  
Channel Copy..............................................................................................39  
Basic operation: Audition mode.................................................. 40  
Basic operation: Channel Level mode........................................ 42  
The "Hidden" Modes........................................................................ 43  
Demonstration mode.................................................................................43  
Real-time Analysis mode (DEQ230D only): ............................................43  
Setup mode..................................................................................................44  
Button combinations..................................................................................49  
Equalization Artifacts.................................................................... 50  
Constant Q vs. Variable Q............................................................. 51  
Chapter Four: Applications.......................................55  
Filtering effects ............................................................................... 56  
Chapter Five: Program Charts.................................59  
DEQ230 Settings Chart.................................................................. 69  
Chapter Six: Troubleshooting...................................71  
Restoring the Factory Programs & Defaults............................ 71  
Line Conditioners and Protectors .............................................. 71  
Care and Maintenance................................................................... 71  
Troubleshooting Index ..............................................................................72  
Specifications...................................................................75  
Audio Performance ....................................................................................75  
Mechanical ...................................................................................................75  
Warranty/Contact Alesis ............................................77  
Alesis Limited Warranty.............................................................................77  
Alesis Contact Information.......................................................................78  
 
2
Introduction  
Welcome!  
Thank you for purchasing the Alesis DEQ230. It is a versatile  
product, and whether it becomes a part of your studio or finds  
its place in your live setup, we know it will serve you well. Since  
1984, we've been designing and building creative tools for the  
audio community. We believe in our products, because we've  
heard the results that creative people like you achieve with them.  
Except as noted, when this  
user guide refers to the  
DEQ230 we will be  
referring to both the  
DEQ230 and the DEQ230D.  
One of Alesis' goals is to make high-quality music technology  
available to everyone. This Reference Manual is an important part  
of that, because in it we try to present the DEQ230’s features in a  
way that is easy to understand and remember. But even beyond  
explaining each feature and parameter, this manual can be a key  
that unlocks an application for the DEQ230 that you may not have  
considered. So we try to write our manuals as carefully as we build  
our products.  
The goal of this manual is to get you the information you need as  
quickly as possible, with a minimum of hassle. We hope we've  
achieved that. If not, please drop us an email and give us your  
suggestions on how we could improve future editions of this  
manual.  
We hope your investment will bring you many years of creative  
enjoyment and help you achieve your goals.  
For more effective  
service and product  
update notices, please  
register your DEQ230  
online at:  
Sincerely,  
The people of Alesis  
support/warranty.htm  
 
3
Introduction  
DEQ230 Key Features  
1. Offers the best of digital technology and analog-style control:  
a graphic display with instant editing of any band or  
combination of bands, plus the ability to store programs  
2. 60 programs total: 30 preset and 30 user-programmable  
3. 48 KHz sampling rate, 24-bit A/D/A, 28-bit internal  
processing  
4. Two channels of equalization, independent or linkable  
5. 30 EQ bands per channel, spanning 25 Hz-20 KHz in 1/3-  
octave increments  
6. +/- 12 dB boost/cut with center detente  
7. Constant Q technology for finer control of audio  
8. LOCK function for "set and forget" situations, which  
prevents accidental reprogramming  
9. AUDITION mode for automated program comparison  
10. Individual Channel Level adjustment per program  
11. Master Level adjustment  
12. [LINK] button for quick creation of matched EQ curves  
13. [BYPASS] button  
14. Configurable editing modes to suit the way you work  
15. Several methods of accelerated program selection  
16. Ability to copy settings from Channel A to Channel B during  
Store procedure  
17. Easy-to-read 7-segment Numeric LED Display  
18. Over 750 Band Gain LEDs, making it easy to read EQ curves  
from a distance  
19. SIGNAL and CLIP LEDs  
20. Balanced input/impedance-balanced output (TRS)  
21. Compact 1-space rackmount profile  
DEQ230D only:  
22. Real-time Analysis (RTA) mode for visual feedback of  
incoming audio signal, with selectable metering modes  
23. S/PDIF input/output, auto-senses incoming digital audio  
24. Clock selectable between 44.1k and 48k sampling rates  
25. MIDI in/out for program changes and sys-ex storage  
26. Balanced input/output (TRS)  
27. +4/-10 operating level switch (rear panel)  
For full operating specifications, see page 75.  
 
4
Introduction  
How to Use This Manual  
This manual is divided into the following sections describing the  
various functions of and applications for the DEQ230. While it's a  
good idea to read through the entire manual once carefully, those  
having general knowledge about audio equipment should use the  
table of contents to look up specific functions.  
Helpful tips and advice are  
highlighted in a shaded box  
like this.  
Chapter 1: Quick Start Guide. If you're already familiar with  
equalization, this will get you started using the DEQ230 right away.  
It's a short guide to the essential elements of hooking it up and  
using it for the first time.  
The names of specific buttons  
on the DEQ230 are printed in  
a bold font and bracketed:  
i.e., the [BYPASS] button.  
Chapter 2: Connections. This section gives detailed instructions for  
connecting the DEQ230 to a variety of typical audio systems.  
Chapter 3: Basics of Equalization. This section explains what an  
equalizer does and explains the function of each of the controls.  
Chapter 4: Applications. Skip to this section for tips on using the  
DEQ230 in a variety of settings.  
Chapter 5: Program Charts. Here you will find the names for all 60  
Factory Programs, with a brief description of each and a small  
graphic representation of the front panel settings.  
Chapter 6: Troubleshooting. Near the end of the manual you will find  
troubleshooting tips and a complete list of the DEQ230’s  
specifications.  
When something important  
appears in the manual, an  
exclamation mark (like the  
one shown at left) will appear  
with some explanatory text.  
This symbol indicates that  
this information is vital when  
operating the DEQ230.  
 
5
Introduction  
This page intentionally left blank  
 
6
Important Safety  
Instructions  
Important Safety Instructions (English)  
Safety symbols used in this product  
This symbol alerts the user that there are important  
operating and maintenance instructions in the literature  
accompanying this unit.  
This symbol warns the user of uninsulated voltage within  
the unit that can cause dangerous electric shocks.  
This symbol warns the user that output connectors contain  
voltages that can cause dangerous electrical shock.  
Please follow these precautions when using  
this product:  
1. Read these instructions.  
2. Keep these instructions.  
3. Heed all warnings.  
4. Follow all instructions.  
5. Do not use this apparatus near water.  
6. Clean only with a damp cloth. Do not spray any liquid cleaner  
onto the faceplate, as this may damage the front panel controls  
or cause a dangerous condition.  
7. Install in accordance with the manufacturer's instructions.  
8. Do not install near any heat sources such as radiators, heat  
registers, stoves, or other apparatus (including amplifiers) that  
produce heat.  
9. Do not defeat the safety purpose of the polarized or  
grounding-type plug. A polarized plug has two blades with one  
wider than the other. A grounding-type plug has two blades  
and a third grounding prong. The wide blade or the third  
prong are provided for your safety. When the provided plug  
does not fit into your outlet, consult an electrician for  
replacement of the obsolete outlet.  
10. Protect the power cord from being walked on or pinched,  
particularly at plugs, convenience receptacles, and the point  
where they exit from the apparatus.  
11. Use only attachments or accessories specified by the  
manufacturer.  
Continued next page  
 
7
Important Safety Instructions  
12. Use only with a cart, stand, bracket, or table designed for use  
with professional audio or music equipment. In any  
installation, make sure that injury or damage will not result  
from cables pulling on the apparatus and its mounting. If a  
cart is used, use caution when moving the cart/apparatus  
combination to avoid injury from tip-over.  
13. Unplug this apparatus during lightning storms or when unused  
for long periods of time.  
14. Refer all servicing to qualified service personnel. Servicing is  
required when the apparatus has been damaged in any way,  
such as when the power-supply cord or plug is damaged, liquid  
has been spilled or objects have fallen into the apparatus, the  
apparatus has been exposed to rain or moisture, does not  
operate normally, or has been dropped.  
15. This unit produces heat when operated normally. Operate in a  
well-ventilated area with at least six inches of clearance from  
peripheral equipment.  
16. This product, in combination with an amplifier and  
headphones or speakers, may be capable of producing sound  
levels that could cause permanent hearing loss. Do not operate  
for a long period of time at a high volume level or at a level  
that is uncomfortable. If you experience any hearing loss or  
ringing in the ears, you should consult an audiologist.  
17. Do not expose the apparatus to dripping or splashing. Do not  
place objects filled with liquids (flower vases, soft drink cans,  
coffee cups) on the apparatus.  
18. WARNING: To reduce the risk of fire or electric shock, do  
not expose this apparatus to rain or moisture.  
 
8
Important Safety Instructions  
Instructions de Sécurité Importantes (French)  
Symboles utilisés dans ce produit  
Ce symbole alèrte l’utilisateur qu’il existe des instructions  
de fonctionnement et de maintenance dans la documentation  
jointe avec ce produit.  
Ce symbole avertit l’utilisateur de la présence d’une  
tension non isolée à l’intérieur de l’appareil pouvant engendrer des  
chocs électriques.  
Ce symbole prévient l'utilisateur de la présence de tensions  
sur les raccordements de sorties, représentant un risque  
d'électrocution.  
Veuillez suivre ces précautions lors de  
l’utilisation de l’appareil:  
1. Lisez ces instructions.  
2. Gardez ces instructions.  
3. Tenez compte de tous les avertissements.  
4. Suivez toutes les instructions.  
5. N’utilisez pas cet allareil à proximité de l’eau.  
6. Ne nettoyez qu’avec un chiffon humide. Il est potentiellement  
dangereux d'utiliser des pulvérisateurs ou nettoyants liquides  
sur cet appareil.  
7. Installez selon les recommandations du constructeur.  
8. Ne pas installer à proximilé de sources de chaleur comme  
radiateurs, cuisinière ou autre appareils (don’t les  
amplificateurs) produisant de la chaleur.  
9. Ne pas enlever la prise de terre du cordon secteur. Une prise  
murale avec terre deux broches et une troisièrme reliée à la  
terre. Cette dernière est présente pour votre sécurité. Si le  
cordon secteur ne rentre pas dans la prise de courant,  
demandez à un électricien qualifié de remplacer la prise.  
10. Evitez de marcher sur le cordon secteur ou de le pincer, en  
particulier au niveau de la prise, et aux endroits où il sor de  
l’appareil.  
11. N’utilisez que des accessoires spécifiés par le constructeur.  
Suite de la page suivante  
 
9
Important Safety Instructions  
12. N’utilisez qu’avec un stand, ou table conçus pour l’utilisation  
d’audio professionnel ou instruments de musique. Dans toute  
installation, veillez de ne rien endommager à cause de câbles  
qui tirent sur des appareils et leur support.  
13. Débranchez l’appareil lors d’un orage ou lorsqu’il n’est pas  
utilisé pendant longtemps.  
14. Faites réparer par un personnel qualifié. Une réparation est  
nécessaire lorsque l’appareil a été endommagé de quelque sorte  
que ce soit, par exemple losrque le cordon secteur ou la prise  
sont endommagés, si du liquide a coulé ou des objets se sont  
introduits dans l’appareil, si celui-ci a été exposé à la pluie ou à  
l’humidité, ne fonctionne pas normalement ou est tombé.  
15. Puisque son fonctionement normale génère de la chaleur,  
placez cet appareil au moins 15cm. des équipments  
péripheriques et assurez que l’emplacement permet la  
circulation de l’air.  
16. Ce produit, utilisé avec un amplificateur et un casque ou des  
enceintes, est capable de produite des niveaux sonores pouvant  
engendrer une perte permanente de l’ouïe. Ne l’utilisez pas  
pendant longtemps à un niveau sonore élevé ou à un niveau  
non confortable. Si vous remarquez une perte de l’ouïe ou un  
bourdonnement dans les oreilles, consultez un spécialiste.  
17. N'exposez pas l'appareil à l'égoutture ou à l'éclaboussement.  
Ne placez pas les objets remplis de liquides (vases à fleur,  
boîtes de boisson non alcoolique, tasses de café) sur l'appareil.  
18. AVERTISSEMENT: Pour réduire le risque du feu ou de  
décharge électrique, n'exposez pas cet appareil à la pluie ou à  
l'humidité.  
 
10  
Important Safety Instructions  
Lesen Sie bitte die folgende Sicherheitshinweise (German)  
Sicherheit Symbole verwendet in diesem  
Produkt  
Dieses Symbol alarmiert den Benutzer, daß es wichtige  
Funktionieren und Wartung Anweisungen in der Literatur gibt, die  
diese Maßeinheit begleitet.  
Dieses Symbol warnt den Benutzer der nicht isolierten  
Spannung innerhalb der Maßeinheit, die gefährliche elektrische  
Schläge verursachen kann.  
Dieses Symbol warnt den Benutzer, dem Ausgabestecker  
Spannungen enthalten, die gefährlichen elektrischen Schlag  
verursachen können.  
Folgen Sie bitte diesenVorkehrungen, wenn  
dieses Produkt verwendet wird:  
1. Lesen Sie die Hinweise.  
2. Halten Sie sich an die Anleitung.  
3. Beachten Sie alle Warnungen.  
4. Beachten Sie alle Hinweise.  
5. Bringen Sie das Gerät nie mit Wasser in Berührung.  
6. Verwenden Sie zur Reinigung nur ein weiches Tuch.  
Verwenden Sie keine flüssigen Reinigungsmittel. Dies kann  
gefährliche Folgen haben.  
7. Halten Sie sich beim Aufbau des Gerätes an die Angaben des  
Herstellers.  
8. Stellen Sie das Gerät nich in der Nähe von Heizkörpern,  
Heizungsklappen oder anderen Wärmequellen (einschließlich  
Verstärkern) auf.  
9. Verfehlen Sie nicht den Zweck des grounging Terminals auf  
dem Netzstecker. Dieses Terminal wird für Ihre Sicherheit zur  
Verfügung gestellt.  
10. Verlegen Sie das Netzkabel des Gerätes niemals so, daß man  
darüber stolpern kann oder daß es gequetscht wird.  
11. Benutzen Sie nur das vom Hersteller empfohlene Zubehör.  
Fortsetzung auf nächster seite  
 
11  
Important Safety Instructions  
12. Verwenden Sie ausschließlich Wagen, Ständer, oder Tische, die  
speziell für professionelle Audio- und Musikinstrumente  
geeignet sind. Achten Sie immer darauf, daß die jeweiligen  
Geräte sicher installiert sind, um Schäden und Verletzungen zu  
vermeiden. Wenn Sie einen Rollwagen benutzen, achten Sie  
darauf, das dieser nicht umkippt, um Verletzungen  
auszuschließen.  
13. Ziehen Sie während eines Gewitters oder wenn Sie das Gerät  
über einen längeren Zeitraum nicht benutzen den Netzstecher  
aus der Steckdose.  
14. Die Wartung sollte nur durch qualifiziertes Fachpersonal  
erfolgen. Die Wartung wird notwendig, wenn das Gerät  
beschädigt wurde oder aber das Stromkabel oder der Stecker,  
Gegenstände oder Flüssigkeit in das Gerät gelangt sind, das  
Gerät dem Regen oder Feuchtigkeit ausgesetzt war und  
deshalb nicht mehr normal arbeitet oder heruntergefallen ist.  
15. Dieses Gerät produziert auch im normalen Betrieb Wärme.  
Achten Sie deshalb auf ausreichende Lüftung mit mindestens  
15 cm Abstand von anderen Geräten.  
16. Dieses Produkt kann in Verbindung mit einem Verstärker und  
Kopfhörern oder Lautsprechern Lautstärkepegel erzeugen, die  
anhaltende Gehörschäden verursachen. Betreiben Sie es nicht  
über längere Zeit mit hoher Lautstärke oder einem Pegel, der  
Ihnen unangenehm is. Wenn Sie ein Nachlassen des Gehörs  
oder ein Klingeln in den Ohren feststellen, sollten Sie einen  
Ohrenarzt aufsuchen.  
17. Setzen Sie den Apparat nicht Bratenfett oder dem Spritzen  
aus. Plazieren Sie die Nachrichten, die mit Flüssigkeiten  
(gefüllt werden Blumevases, Getränkdosen, Kaffeetassen)  
nicht auf den Apparat.  
18. WARNING: um die Gefahr des Feuers oder des elektrischen  
Schlages zu verringern, setzen Sie diesen Apparat nicht Regen  
oder Feuchtigkeit aus.  
 
12  
Important Safety Instructions  
CE Declaration Of Conformity  
See our website at:  
FCC Compliance Statement  
This device complies with Part 15 of the FCC rules. Operation is  
subject to the following two conditions: (1) This device may not  
cause harmful interference and (2) this device must accept any  
interference received, including interference that may cause  
undesired operation.  
NOTE: This equipment has been tested and found to comply with  
the limits for a Class B digital device, pursuant to Part 15 of the  
FCC Rules. These limits are designed to provide reasonable  
protection against harmful interference in a residential installation.  
This equipment generates, uses and can radiate radio frequency  
energy and, if not installed and used in accordance with the  
instructions, may cause harmful interference to radio  
communications. However, there is no guarantee that interference  
will not occur in a particular installation. If this equipment does  
cause harmful interference to radio or television reception, which  
can be determined by turning the equipment off and on, the user  
is encouraged to try to correct the interference by one or more of  
the following measures:  
-- Reorient or relocate the receiving antenna.  
-- Increase the separation between the equipment and receiver.  
-- Connect the equipment into an outlet on a circuit different from  
that to which the receiver is connected.  
-- Consult the dealer or an experienced radio/TV technician for  
help.  
 
13  
Important Safety Instructions  
This page intentionally left blank  
 
14  
1 Quick Start Guide  
If you can't wait to get started  
The Alesis DEQ230 is a unique product, but its basic hookup and  
operation are similar to other equalizers in most respects. If you're  
experienced with signal processors, this chapter is a “shorthand”  
guide for those who want to start using the DEQ230 right away. If  
you have questions about any of the features, don’t worry – we’ll  
cover everything in greater detail in later chapters.  
If you're new to signal  
processing, start with the more  
detailed instructions for  
hookup and operation found in  
the next chapter.  
Step 1: Hook it up to a mixer  
The DEQ230’s power will turn  
on automatically once its AC  
cable is plugged in, so be sure  
to press the [POWER] switch  
to turn the unit off while you’re  
connecting it to your other  
equipment.  
1. Plug the POWER jack on the back of the DEQ230 into a  
grounded AC power source with the supplied power cable.  
2. Using a pair of high-quality cables, plug the left and right main  
outputs of a non-powered mixer into the CHAN A and  
CHAN B INPUTs on the back of the DEQ230.  
3. Connect another pair of cables to the CHAN A and CHAN  
B OUTPUTs of the DEQ230 and plug them into your  
amplification system or a pair of powered monitors.  
4. Press the [POWER] switch on the front of the DEQ230 to  
power up the unit.  
When connecting the DEQ230  
to other equipment, make sure  
all gear has been turned off.  
Also, to protect your speakers,  
be certain your amplifier(s)  
are turned all the way down  
before turning your equipment  
back on.  
5. If the LINK LED is not lit, you may want to press the  
[LINK/EXIT] button on the front of the DEQ230.  
That way you’ll hear the changes you make with Channel A  
affect both channels of audio at once.  
 
15  
1 Quick Start Guide  
Step 2: Try some equalization  
Play some signal into the unit  
While learning the unit, you should play a CD or a multitrack  
source into the equalizer. Choose a song or musical passage with a  
fairly consistent level, so you can take your time experimenting  
with the different features.  
1. Put the mixer’s main faders all the way down so you don’t  
distort the unit by sending it too much signal.  
2. Select program 00 on the DEQ230. The fastest way to do this  
is to press the [DOWN] and [UP] buttons at the same time.  
This will call up a program with all frequencies set to 0 dB,  
which will allow you to hear the changes you make to the  
audio more easily.  
3. Begin playing your source material. Bring the mixer’s main  
faders up gradually until the green LED over the word  
SIGNAL begins to light up on each side. Carefully increase the  
mixer’s output level until the green LEDs are lit most of the  
time. If the red LEDs light up at all, back the mixer’s output  
level down until they stop lighting up. This is important,  
because the red LEDs indicate that the signal is clipping on  
that channel.  
Remember: if one or both of the  
red LEDs light up, that means  
the signal is clipping. To  
prevent this, reduce the level  
being sent to the proper  
channel.  
4. Press one of the [BAND SELECT] buttons to select a  
frequency. One of the LEDs above that button will begin to  
blink.  
5. Use the [DOWN] and [UP] buttons on either side of the  
[POWER] switch to decrease or increase the chosen  
frequency. If desired, select another frequency and repeat this  
process.  
6. Press the [BYPASS] button to hear the signal without the  
equalization effect. Press it again to return to the EQ’d signal.  
Step 3: Store the Program  
Once you have created an interesting program, you can save it to  
one of the 30 User program locations. Here’s how to do this:  
Programs 55-59 have been left  
“blank” so you have places to  
store your new programs right  
away.  
1. Press the [STORE] button to enter Store mode.  
2. Use the [DOWN/UP] buttons to select the new location for  
the edited program. For your convenience, programs 55-59  
have been left “blank” so you can store your editing  
experiments somewhere without fear of overwriting a  
program you might want to use later.  
3. Press the [STORE] button again to store the program to the  
new location.  
For a detailed explanation on how to use this mode, see page 38.  
 
16  
Quick Start Guide 1  
 
17  
1 Quick Start Guide  
 
18  
2 Connections  
Unpacking and Inspection  
Your DEQ230 was packed carefully at the factory. The shipping  
carton was designed to protect the unit during transit. Please keep  
this carton in the highly unlikely event that you need to return the  
DEQ230 for servicing.  
The shipping carton should contain the following items:  
DEQ230 with the same serial number as shown on shipping  
carton  
A/C power supply adapter (DEQ230 only)  
A/C power cable (DEQ230D only)  
This instruction manual  
Installing in a Rack  
The DEQ230 may be simply set on a table, or installed in a  
standard 19" audio equipment rack.  
Thermal Considerations in Rack  
Mounting  
The DEQ230 can be mounted in an equipment rack (occupying  
one rack space) or placed on a table or shelf. When you install it,  
keep in mind that heat is the greatest enemy of electronic  
equipment. Please observe the following:  
The DEQ230 is designed to perform properly over a range of  
ambient temperatures from 10° C to +40° C (50° F to 104° F),  
in up to 80% non-condensing humidity. These are not absolute  
limits, but Alesis cannot guarantee that the DEQ230 will meet  
its published specs or remain reliable if operated outside of  
these ranges.  
Always allow adequate ventilation behind the DEQ230. Do not  
seal any enclosure that holds this unit. It is not necessary to  
leave an empty rack space above or below the DEQ230.  
However, if your environment is unusually warm and not air  
conditioned, space between units will help the units run cooler.  
 
19  
2 Connections  
AC Power Hookup  
The DEQ230D has what’s known as a “switching power supply.”  
This means it will detect any standard line voltage from 90 to 230  
volts, 50-60 Hz, and adapt itself to that. All you need is the proper  
A/C cable for the country in which you find yourself. Just plug the  
"female" end of the power cable into the DEQ230D’s POWER  
receptacle and the “male” end into a good quality, noise-free A/C  
power source.  
The DEQ230 will work with any standard line voltage from 100 to  
240 volts as long as the appropriate detachable power supply  
adapter is used. The DEQ230 has been shipped with the suitable  
adapter for the line voltage in your area.  
Plug the "barrel" end of an approved power supply adapter into  
the DEQ230’s POWER 9V AC jack and the transformer end into  
a good quality, noise-free AC power source of the proper rating.  
The DEQ230 is specifically  
designed to be powered by  
the power supply adapter we  
have included. Do not  
substitute any other type of  
power supply adapter. If a  
replacement is needed, one  
may be purchased from your  
Alesis dealer or from the  
Alesis Parts department.  
To use the DEQ230 in another country:  
Your DEQ230 was supplied with the correct power supply adapter  
for your country or local area. If you plan to travel with it to  
another country, obtain an Alesis AC power supply adapter  
compatible with the outlets used in the other country and use it in  
place of the supplied adapter. These can be obtained through your  
Alesis dealer or through the Alesis Parts department.  
 
20  
Connections 2  
Connecting Inputs and Outputs  
Connecting to the Channel or Main Inserts  
of a mixing console  
Unbalanced I/O  
When connecting audio  
cables and/or turning power  
on and off, please make sure  
that your amplifiers are  
turned off or down to prevent  
damage to your speakers.  
Most mixing consoles have insert jacks near the main outputs and  
for each channel as well. These are typically Tip-Ring-Sleeve (TRS)  
jacks with the send and return on the same jack. To use the  
DEQ230 as an effects insert device, you will need an insert cable  
(not included).  
This cable splits the TRS insert jack into two unbalanced mono  
connectors. Usually, the tip is wired to the "Send" connector,  
which plugs into one INPUT of the equalizer, and the ring is  
wired to the "Return" connector, which plugs into the  
corresponding OUTPUT of the equalizer. However, the wiring  
of the insert jacks is different on some recording consoles, which  
means that the input/output relationship may be reversed. Check  
your mixer’s Reference Manual to be sure, or just try it both ways –  
this won’t damage the DEQ230.  
If your mixer does not have  
insert jacks available at its  
main outputs, simply connect  
the main outputs of your non-  
powered mixer to the inputs  
of the DEQ230, then connect  
the outputs of the equalizer to  
the inputs of your mixdown  
recorder or amplified  
monitoring system.  
 
21  
2 Connections  
Mono connections  
This example shows how to connect the DEQ230 to one mono  
source. You can use this method to connect two mono sources or  
one stereo source to the DEQ230. You would need two insert  
cables to make both of these connections.  
Since the DEQ230 has two  
channels, A and B, you can  
connect two independent  
sources. For example, you  
could use channel A to EQ  
the rhythm guitar and  
channel B to EQ the bass  
guitar. Or use channel A on  
the kick drum and channel B  
for the snare drum.  
Stereo connections  
Use two insert cables to connect the DEQ230 to the main L/R  
bus in the same way you would connect it to a pair of channel  
inserts. Simply connect one insert cable to the left main insert of  
the mixer, and connect the two mono jacks to the CHAN A  
INPUT and OUTPUT of the DEQ230. Use another insert cable  
to connect the right main insert to the CHAN B INPUT and  
OUTPUT of the DEQ230.  
You can also simply connect the balanced main outputs of the  
mixer to the inputs of the DEQ230, then connect the outputs of  
the equalizer to the inputs of your mixdown recorder, monitor  
system, etc.  
Never place the equalizer  
between the power amp and  
the speakers, as the high-  
powered levels created by  
the power amp will damage  
the DEQ230.  
Balanced I/O  
Some recording consoles have separate balanced jacks for the  
sends and returns instead of a single TRS jack. If your recording  
console has these connections, use a balanced TRS cable to  
connect the insert send to the INPUT of the equalizer, and  
another balanced TRS cable to connect the equalizer OUTPUT to  
the insert return.  
Modern production values  
sometimes lead to the heavy  
use of compression during  
the mastering process. When  
processing CD audio, you  
may find it necessary at  
times to lower the Channel  
Level of the active program  
so as to avoid clipping the  
output stage of the DEQ230.  
This will allow additional  
headroom for more  
Operating Levels  
The DEQ230D can operate in either a +4dBu or –10dBV setting.  
A rear panel switch allows you to configure the unit to your audio  
environment.  
The DEQ230 is a “line level” device, which means that it operates  
at a nominal level of –10dBV, with a maximum input level of  
+8dBV. Some equipment operates at a nominal level of +4dBu,  
and can run the signal up to +24dBu. To prevent clipping, reduce  
the level being sent from this equipment.  
extensive equalization. See  
pg. 42 for details on the  
Channel Level function.  
If you are unsure about the nominal operating level of the  
equipment to which you will be connecting the DEQ230, refer to  
the Reference Manual for that equipment.  
 
22  
Connections 2  
Connecting to the inserts on an instrument  
amplifier  
Unbalanced I/O  
The insert sends on a guitar or bass amp are usually labeled  
"effects send and return" or "insert send and return." This allows  
your instrument to be boosted to line level before the signal is sent  
to the equalizer, processed, and returned to the power amp.  
Another method would be to insert the DEQ230 between the  
preamp and the power amp, if you are using a two-piece system.  
You should never put the equalizer between the power amp and  
the speaker, as the high-powered levels created by the power amp  
will damage the unit.  
Don't use line transformers!  
Many XLR-to-1/4" adapters  
sold at electronics stores are  
NOT adapters, but  
transformers (and very low  
quality transformers at that).  
Don't use these on the output  
of the DEQ230—they're  
unnecessary and generally  
sound awful because they  
don't have the headroom to  
handle the DEQ230's output.  
Get a hard-wired adapter or  
cable from your professional  
audio dealer, or make one  
yourself from components.  
Connecting to equipment with XLR inputs  
and outputs  
If you are connecting the DEQ230 to a product with XLR  
balanced inputs and outputs, you will need to convert this signal to  
a TRS balanced connector. Make sure that pin 2 of the XLR  
connector is connected to the tip of the TRS adapter, and pin 3 is  
connected to the sleeve.  
Connecting to equipment with S/PDIF  
inputs and outputs (DEQ230D only)  
The DEQ230D has the added capability of receiving and  
transmitting its audio signal in the digital domain. This is done  
through a pair of coaxial connectors (also known as RCA jacks)  
found on the rear panel. The jacks are labeled S/PDIF In/Out:  
each carries two channels of audio, so both Channel A and  
Channel B are handled by a single cable in each direction.  
Using the S/PDIF jacks to connect to an external device such as  
the Alesis MasterLink is very easy, because the DEQ230D will  
automatically switch over to the S/PDIF input when it senses that  
a valid digital signal is present.  
 
23  
2 Connections  
There are three ways to connect the DEQ230D with another  
digital audio device:  
Analog Signal In, Digital Signal Out  
A potential use for this setup would be if you are running your  
recorded tracks into a mixer that only has an analog output, but  
your mixdown deck has S/PDIF inputs. Use the DEQ230D to put  
that finishing touch on the mix, and then use it as a digital audio  
interface into the mixdown deck. In doing this you ensure the  
cleanest possible connection between the DEQ230D and the  
mixdown deck.  
To use the DEQ230D in this way, connect the S/PDIF Output of  
the DEQ230D to the S/PDIF Input of the receiving device.  
Digital Signal In, Analog Signal Out  
This would be the method to use, for example, if you have a mixer  
with a digital output for its main mix and an amplification system  
that only has analog inputs. With this setup you would be able to  
pass the audio to the DEQ230D in the digital domain, shape the  
signal using its 28-bit internal processing, and then send the result  
to the amplification system.  
Of course, you could substitute a CD player or DAT deck for the  
mixer in the above example, and/or substitute a mixdown deck or  
a couple of channels on a mixer for the amplification system.  
In this case, connect the S/PDIF Output of the transmitting  
device to the S/PDIF Input of the DEQ230D.  
Digital Signal In, Digital Signal Out  
In cases where every device in your audio chain has a digital audio  
input and output, the DEQ230D is right at home. Simply pass the  
audio from the transmitting device’s S/PDIF Output into the  
DEQ230D’s S/PDIF Input, use it to sculpt the signal, and then  
pass the audio on to the next device by connecting the  
DEQ230D’s S/PDIF Output to the S/PDIF Input of the  
receiving device.  
Operating the DEQ230D in any of the three configurations  
described above is really no different from using it in a completely  
analog system. For that reason, from this point on in the manual  
we will make no distinction between operating the DEQ230D in  
the digital or analog domains.  
 
24  
Connections 2  
About Audio Cables  
The connections between the DEQ230 and your studio are your  
music’s lifeline, so use only high quality cables. These should be  
low-capacitance shielded cables with a stranded (not solid) internal  
conductor and a low-resistance shield. Although quality cables cost  
more, they do make a difference.  
Route cables to the DEQ230 correctly by  
observing the following precautions:  
Do not bundle audio cables with AC power cords.  
Avoid running audio cables near sources of electromagnetic  
interference such as transformers, monitors, computers, etc.  
Do not place cables where they can be stepped on. Stepping on  
a cable may not cause immediate damage, but it can compress  
the insulation between the center conductor and shield,  
degrading the cable’s performance, or reduce the cable’s  
reliability.  
Avoid twisting the cable or having it make sharp, right angle  
turns.  
Never unplug a cable by pulling on the wire itself. Always  
unplug by grasping the body of the plug firmly and pulling  
directly outward.  
And most importantly, keep connectors clean. Every few months,  
unplug them and wipe off oxidation with a clean cloth soaked in  
alcohol or contact cleaner. Insert the plugs in the jacks a few times  
to clean the internal jack contacts.  
Although Alesis does not endorse any specific product, chemicals  
such as Tweek (also known as Stabilant) and Cramolin, when  
applied to electrical connectors, are claimed to improve the  
electrical contact between connectors.  
 
25  
2 Connections  
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26  
3 Basics of Equalization  
This section will explain how equalization works, and explain the  
functions of the DEQ230’s controls.  
What is equalization?  
An equalizer boosts or cuts a frequency range. The DEQ230 is a  
graphic equalizer, which means it has many fixed frequency bands  
that can be cut or boosted. The term "graphic" is appropriate  
because the combined settings of the bands often resemble a  
curve, or a "graph." Thus it is often possible to know what the unit  
is doing to the sound simply by looking at it from a distance. The  
other type of equalizer, a parametric equalizer, can sweep the  
frequency bands and adjust the frequency range affected by the cut  
or boost of each band. Alesis sells a parametric equalizer called the  
PEQ-450.  
The most basic level of control on a graphic equalizer is the gain  
setting for a band. Each of the bands represents a pre-determined  
frequency range, and its gain setting controls the amount of boost  
or cut for that frequency range. A setting of 0 dB means that the  
signal will not be affected in the area of those audio frequencies.  
Depending on the program material, boosting or cutting just one  
frequency can have a significant impact on the sound. When all of  
the frequency bands are taken together, the impact can be huge.  
Equalization is used for:  
Adjusting the timbre of an instrument, voice, mix or effect  
Cutting or boosting frequencies to make a source easier to mix  
with other tracks  
Compensating for a less-than-ideal recording  
Compensating for less-than-ideal control room or auditorium  
acoustics  
Creating a filter effect  
Eliminating buzz, noise or hum  
Equalizers can make your recorded tracks sound polished and  
professional. Chapter 4 will describe some specific settings for  
various instruments and applications.  
 
27  
3 Basics of Equalization  
Description of the Controls  
There are thirty buttons side-by-side on each channel of the  
DEQ230. These are the [BAND SELECT] buttons. Above each  
button is a number like "25" or "8k." These stand for the audio  
frequencies, measured in Hertz (Hz), which are selected for editing  
by the [BAND SELECT] buttons below them.  
Situated between the [BAND SELECT] buttons for Channel A  
and Channel B you will find three larger buttons. The one in the  
very middle is the [POWER] button. On either side of that are  
the [DOWN] and [UP] buttons, which are used to edit the gain  
amount of the frequency you have selected with the [BAND  
SELECT] buttons. (It is also possible to select and edit several  
frequencies at once; more about this later.) The [DOWN/UP]  
buttons are also used to select programs in Program mode.  
Directly above these three buttons are three more buttons: the  
[BYPASS], [STORE], and [LINK/EXIT] buttons. Their  
functions are as follows:  
[BYPASS]  
Bypass mode “hides” the  
effect the EQ and Channel  
Level controls have on the  
audio. However, the Master  
Level function from Setup  
mode is unaffected by the  
[BYPASS] button. For more  
information about the  
When this button is first pressed, a red LED will light. This means  
the DEQ230 is in Bypass mode. As long as this LED is lit,  
incoming audio will pass through the unit without being affected  
by the DEQ230. This is useful for comparing the "equalized"  
signal with the original signal so you can decide if you like the edit  
you made. Press the button again to get out of Bypass mode and  
hear the effect.  
relationship between Channel  
Level and Master Level, see  
page 45.  
[STORE]  
Once you have made an edit you would like to keep, press this  
button to enter Store mode. From there you can decide which of  
the 30 User locations will become the new home for the edited  
Program. You can also copy the settings from Channel A to  
Channel B as you store a program. For more information on this  
function, see page 38.  
[LINK/EXIT]  
This button serves a dual purpose:  
1. While in Program mode, pressing this button will cause the  
settings for Channel B to "mirror" the settings for Channel A.  
Any further edits you make to a band on Channel A will also  
happen to that same band on Channel B. This is useful for  
quickly setting up a program without having to make  
independent adjustments for each channel.  
It is possible to copy the  
settings from Channel A to  
Channel B during the Store  
process so they are not merely  
“mirrored.” See page 39 for  
further details.  
2. If you’re in the middle of some other activity, such as editing  
or storing, pressing this button will allow you to "exit" to  
Program mode.  
 
28  
Basics of Equalization 3  
Description of the Basic Modes  
Program mode  
When this manual refers to Program mode, we mean the very top  
level of functionality of the DEQ230. Program mode is where you  
are when it is possible to use the [DOWN/UP] buttons to select  
between the different programs that reside in the unit. In this  
mode, you have access to the 30 Preset programs and 30 User  
programs.  
A Program consists of all of the settings on the front panel, with  
the exception of the status of the [BYPASS] button. The things  
stored in memory and recalled when you select a program are:  
The gain settings of all 30 bands for both channel A and  
channel B  
The status of the [LINK/EXIT] button  
The gain settings for all 30 bands of channel B, even if the  
Link function is active. They are merely "hidden" by the Link  
function.  
The individual Channel Level settings for channels A and B  
If the DEQ230 has been in some other mode, pushing the  
[LINK/EXIT] button will return it to Program mode. If you see  
a dot to the right of the Program number LEDs, that means the  
program has been edited. Be certain to save any changes you've  
made that you would like to keep! To learn how to Store an edited  
program, turn to page 38.  
Edit mode  
While in Program mode, if you push one of the [BAND  
SELECT] buttons the unit will enter Edit mode. You can tell you  
are in Edit mode when you see one or more of the LEDs above  
the [BAND SELECT] buttons blinking. Whichever bands have a  
blinking LED are the ones that will be boosted or cut when you  
use the [DOWN] and [UP] buttons.  
Pressing the [DOWN/UP]  
buttons at the same time will  
reset the band you have  
selected to 0 dB.  
After you have edited a frequency or an Edit Group (a group of  
frequencies), if you push the [LINK/EXIT] button you will be  
returned to Program mode. If you made any changes, you will see  
a dot to the right of the Program number LEDs. But be certain to  
save any changes you've made that you would like to keep! That is  
where Store mode comes in.  
Store mode  
Pressing the [STORE] button takes you into Store mode. From  
here you can decide which of the 30 User Programs will become  
the new location for the edited program. You may also instruct the  
DEQ230 to copy the settings from Channel A to Channel B  
during the Store process. For information on how to perform  
either of these procedures, see page 38.  
 
29  
3 Basics of Equalization  
Bypass mode  
This mode is nearly as simple as it sounds: push the [BYPASS]  
button and the DEQ230 will let you hear the non-equalized audio.  
But there’s a bit more to it than that. There are also two gain  
adjustment stages that can be used to compensate for a reduction  
or increase in signal level caused by the equalization curve being  
used. The value for one of these stages (Channel Level) is saved  
along with the EQ settings when the program is stored; the value  
for the other stage (Master Level) is not. So what Bypass mode  
really is doing is causing the audio to “pass by” the processing  
stages that are stored as a part of the program.  
You’ll find a description of  
Channel Level mode further  
down on this page. For a  
description of the Master Level  
function, turn to page 45.  
Here is a diagram that shows the relationship of each of the stages  
in the DEQ230’s signal processing chain:  
Audition mode  
Audition mode allows you to choose specific programs and place  
them into the Audition List. From there you can more easily  
audition only those programs you want to hear for a particular  
audio source and "jump over" the ones you do not. To learn how  
to use this mode, see page 40.  
Channel Level mode  
If you are running two different instruments into channels A and  
B, you may be experiencing drastically different signal levels in  
each Channel. Channel Level mode can be used to adjust the  
output of channels A and B independently.  
This mode is also useful when processing a stereo signal. If the  
combination of the source material and extreme EQ settings is  
causing the output of the DEQ230 to clip, Channel Level mode  
can be used to adjust the output of channels A and B  
simultaneously.  
Unlike the Master Level function in Setup mode, the settings for  
Channel Level mode are stored with each program. To learn how  
to use this mode, see page 42.  
 
30  
Basics of Equalization 3  
Basic operation: Program mode  
Program mode is where to be if you want to call up another  
program, or if you just want to know the number of the program  
you are using. The DEQ230 has 60 programs in all: 30 Preset  
programs and 30 User programs. The Preset programs are the  
ones numbered 00-29, while the User programs are numbered 30-  
59. You can use the Preset programs as starting points for your  
own programs, but you cannot store your creations back on top of  
a Preset program. That's what the User programs are for.  
Navigation in Program mode is a breeze. First, if you're not in  
Program mode, get there by pressing the [LINK/EXIT] button.  
The large LED readout will show you the number of the current  
program. All you have to do to call up a new Program is press one  
of the [DOWN/UP] buttons.  
If you hold down one of the [DOWN/UP] buttons for a few  
seconds, the DEQ230 will begin to race through the programs.  
That's one way to get from Program 10 to Program 40 more  
quickly, for example. You'll also notice that it doesn't matter  
whether you go up or down; you can get from Program 10 to  
Program 40 going either direction.  
Pressing the [DOWN/UP]  
buttons at the same time  
while in Program mode will  
call up Program 00, the  
default program.  
But there's a way to get around Program mode even more quickly.  
If you press and hold the [UP] button while you press the  
[DOWN] button, the DEQ230 will jump to Program 00. If you  
keep pressing the [DOWN] button, the DEQ230 will jump  
backward through the programs in increments of 10 (50, 40, 30,  
etc.). Likewise, if you press and hold the [DOWN] button while  
you press the [UP] button, the DEQ230 will jump to Program 00.  
And if you keep pressing the [UP] button, the DEQ230 will jump  
forward through the programs in increments of 10 (10, 20, 30,  
etc.).  
Once you get the hang of those two methods of navigation, you  
can reach any program in the unit's memory in two seconds or  
less.  
 
31  
3 Basics of Equalization  
Basic operation: Edit mode  
If you're not already there, exit to Program mode by using the  
[LINK/EXIT] button. Then select program 00 on the DEQ230  
by pressing the [DOWN] and [UP] buttons at the same time.  
Use Program 00 if you want to  
start with a “clean slate” and  
build a new program from the  
ground up.  
Program 00 is a "flat" program, and it's easy to see why it's called  
that: the gain setting for every band is 0 dB. Calling up this  
program is almost the same as pressing the Bypass button, in that  
the audio passing through the unit will not be equalized in any way.  
Of course, the difference is that you can edit the program and hear  
the changes that you make. If you don't already know what kind  
of EQ you're looking for, this may be a good place to start.  
If the Numeric LED Display  
shows “Li” when you press  
[BAND SELECT] buttons on  
Channel B, it means the  
channels are linked. Either  
make the edits on Channel A,  
or return to Program mode  
and press [LINK/EXIT] to  
unlink the channels.  
Single Band Edit  
Pressing a [BAND SELECT] button puts the DEQ230 into Edit  
mode. The Numeric LED Display will change from the current  
program number to the gain value in decibels (dB) of the band  
you just selected. In addition, one of the Band Gain LEDs above  
that [BAND SELECT] button will start blinking. If the gain  
value of that band is 0 dB, the green LED will blink. This means  
there is no gain change occurring in this frequency range. If it is  
higher or lower than that, one of the yellow LEDs will blink. This  
indicates that some amount of cut or boost is happening.  
Use the [DOWN/UP] buttons to change the gain value of that  
band. The [DOWN] button will lower the gain value, or "cut" the  
chosen frequency; the [UP] button will raise the gain value, or  
"boost" the frequency. Pressing both the [DOWN] and [UP]  
buttons at the same time will reset the gain value of the frequency  
to 0dB. There is an overall range of +/- 12 dB of gain change  
available.  
After resetting a band’s value,  
you can change the level of  
that band in 2 dB increments if  
you hold one of the  
[DOWN/UP] buttons and  
press the opposite button  
repeatedly. This can help you  
set up a curve with greater  
accuracy and speed.  
Band Solo  
The DEQ230 has a handy feature called Band Solo that allows you  
to “isolate” a given frequency while you are editing. This can help  
you determine exactly which band you need to highlight or de-  
emphasize. It’s simple to do:  
1. Select a band by pressing and holding its [BAND SELECT]  
button.  
2. Press the [UP] button. You’ll see the LED for that band  
jump to +12 dB.  
3. Press the [DOWN] button. The LED for that band will  
jump to –12 dB.  
4. Release the [BAND SELECT] button and the value of that  
band will be unchanged.  
This only works with one band at a time, but you’ll find it to be a  
very helpful feature.  
To exit Edit mode, press the [LINK/EXIT] button. This will  
return the DEQ230 to Program mode. The same thing will  
happen if you de-select the single band you have selected.  
 
32  
Basics of Equalization 3  
Band Gain Cut/Boost Ranges  
Whether you are cutting or boosting a band, the first 10 dB of  
change happens in 0.5 dB increments. The last 2 dB of change,  
going from +/-10 dB to +/-12 dB, happens in increments of 1.0  
dB. So as you make the change, the Numeric LED Display will  
show you values like this: 0.5, 1.0, 1.5, 2.0, 2.5 ... 9.0, 9.5, 10, 11,  
12.  
It’s not possible to show a minus sign in the LED display for  
negative gain values. So when you're pushing the [DOWN]  
button, you'll see the same values: 0.5, 1.0, 1.5, 2.0, 2.5 ... 9.0, 9.5,  
10, 11, 12. But if there's any doubt in your mind about which away  
you're going, the Band Gain LED will clue you in. As soon as you  
move 0.5 dB away from 0, the LED for that band will change from  
green to yellow. If you are cutting the frequency, the -2 dB LED  
will light. If you are boosting the frequency, the +2 dB LED will  
light. And on it goes until you reach the maximum value in either  
direction.  
The resolution of the gain increments is higher than the number  
of gain LEDs in each band on the front panel can fully display.  
Therefore, you may make 0.5dB changes to gain and a band's Gain  
LED may not change. The following table shows the amount of  
change in dB it takes to light each of the Band Gain LEDs:  
LED  
Gain change  
+ 12 dB  
+ 12 dB  
+ 10 dB  
+ 8 dB  
+ 6 dB  
+ 4 dB  
+ 2 dB  
0 dB  
9.5 – 11 dB  
7.5 - 9.0 dB  
5.5 - 7.0 dB  
3.5 - 5.0 dB  
0.5 - 3.0 dB  
0 dB  
Remember, if you want to  
keep the edited program,  
be sure to store it to one of  
the User locations. For  
instructions on how to do  
this, turn to page 38.  
- 2 dB  
- 4 dB  
- 6 dB  
- 8 dB  
- 10 dB  
- 12 dB  
0.5 - 3.0 dB  
3.5 - 5.0 dB  
5.5 - 7.0 dB  
7.5 - 9.0 dB  
9.5 - 11 dB  
- 12 dB  
 
33  
3 Basics of Equalization  
Multiple Band Edit  
Selecting an Edit Group  
Pressing a [BAND SELECT] button puts the DEQ230 into Edit  
mode. And until you press one of the [DOWN/UP] buttons, you  
can keep pressing [BAND SELECT] buttons until you have  
several of them selected simultaneously. This is called selecting an  
Edit Group. An Edit Group can be made up of any number of  
bands from both channels if the Link LED is not active.  
If the Numeric LED Display  
shows “Li” when you press  
[BAND SELECT] buttons on  
Channel B, it means the  
channels are linked. Either  
make the edits on Channel A,  
or return to Program mode  
and press [LINK/EXIT] to  
unlink the channels.  
The Relative Gain Display  
When you pressed the first [BAND SELECT] button, two things  
happened: the Numeric LED Display changed to show the gain  
value of that band, and one of the corresponding Band Gain  
LEDs started to blink. Then when you pressed the second  
[BAND SELECT] button, two more things happened: the  
Numeric LED Display changed to show the number "0," and a  
second Band Gain LED started to blink. Each additional [BAND  
SELECT] button you press adds a band and a blinking LED to  
the Edit Group.  
In Multiple Band Edit mode,  
pressing the [DOWN/UP]  
buttons at the same time will  
reset the Relative Gain  
Display to 0. This resets the  
bands within the Edit Group  
back to their original values.  
From this point you can  
change the Relative Gain of  
the Edit Group in 2 dB  
But why did the Numeric LED Display change to a zero? Because,  
once you have selected an Edit Group, you can cut or boost the  
gain of all of the bands in the Edit Group at once. They will move  
up or down in proportion to one another. The zero in the display  
represents a "benchmark" for the amount of gain change that  
happens to the Edit Group. The 7-segment LEDs can't display the  
gain values of each band within the Edit Group all at once, so if  
you raise the overall level of the Edit Group by 2 dB, that's the  
number you will see. The function of the display in this case is to  
tell you the Relative Gain amount.  
increments by holding one of  
the [DOWN/UP] buttons and  
pressing the other one  
For the sake of clarity, when this manual is describing what is  
shown in the 7-segment LEDs while changing the overall gain  
value of the Edit Group, we will refer to it as the Relative Gain  
display.  
repeatedly.  
Here’s an example: let's say you have selected the bands at 4k and  
5k as your Edit Group. The initial gain value for 4k is +2 dB and  
the gain value for 5k is -2 dB. The Relative Gain display at this  
point will read "0." If you press the [UP] button four times, the  
final value of the Relative Gain display will be a "2." The actual  
gain values for 4k and 5k are now +4 dB and 0 dB, respectively,  
which will be indicated by their Band Gain LEDs.  
For maximum preservation of  
fidelity of the input signal, the  
largest number of bands in a  
channel should be set to 0 dB.  
For example, if you have more  
than half of your bands set to  
some cut amount and the  
majority of those cut  
Proportional Gain Memory  
It's possible you may see numbers as large as 24 in the Relative  
Gain display. This is due to a very powerful aspect of the Relative  
Gain feature, and it will require some careful explanation.  
frequencies are at -4 dB, then  
select all bands and  
compensate by +4 dB.  
Here's another example. Let's say you have two bands selected.  
The first band is set to 0 dB, and the second band is set to -12 dB.  
The Relative Gain display reads "0." If you press the [UP] button  
and keep holding it, you will see that number change from 0 to 12  
(see fig. 1 on page 35). But it won't stop at 12; it will keep racing  
 
34  
Basics of Equalization 3  
upward until it reaches 24. This is because that's how far the band  
that was set to -12 dB had to travel until it hit the "ceiling," or + 12  
dB (see fig. 2).  
But what about the band that was set to 0 dB originally...was it  
boosted to +24 dB? The answer is, "Yes and no." It was, in the  
sense that the DEQ230 keeps track of the proportional values of  
the bands, even if they exceed the +/-12 dB limit of gain change  
for a frequency. But the audible audio gain is limited to +/-12 dB.  
Remember, pressing the  
[DOWN/UP] buttons at the  
same time will reset the  
Relative Gain Display to 0.  
From this point you can  
change the Relative Gain of  
the Edit Group in 2 dB  
increments by holding one of  
the [DOWN/UP] buttons and  
pressing the other one  
repeatedly. This can be a real  
time-saver if you want to get  
from a Relative Gain value of  
+24 to a value of –24!  
The reason the DEQ230 keeps track of the gain relationship  
between the bands in the Edit Group is simple. It's so you can  
change your mind, pull them back down to values within the +/-  
12 dB limit, and still have them be the same distance apart!  
For example: let's say you decided these frequencies have been  
boosted too much, and you cut them by 12 dB. At this point the  
Relative Gain display would read "12," with band one's Gain LED  
at +12 dB and band two's Gain LED at 0 dB (as in fig. 1). So far  
you haven't really reduced the gain of the first band, because it's  
still at +12 dB. You still want to bring it down a bit, so you take  
both frequencies down another 3 dB. So now the Relative Gain  
display would read "9," with band one's Gain value at +9 dB and  
band two's Gain value at -3 dB. And now you can see that the gain  
relationship between the two bands was preserved; they're still 12  
dB apart.  
 
35  
3 Basics of Equalization  
One important note, though; Proportional Gain Memory is only  
temporary. If you have run one or more bands "past" the +/-12  
dB limit and then you exit Edit mode for any reason (such as to  
store the program), the gain value of those bands will be  
remembered as +/-12 dB (whichever was the value that was last  
reached for those bands).  
The Limits of Relative Gain  
There will be times when the Relative Gain display will not go all  
of the way up or down to a value of 24. This is because the  
DEQ230 takes into account the gain setting of all of the bands  
when an Edit Group is formed. If the highest gain setting of any  
band in the Edit Group is + 6 dB, then from there down to -12 dB  
is only 18 dB. So this is the largest number you will see in the  
Relative Gain display if you run the relative gain value all the way  
down (see fig. 3 and 4).  
 
36  
Basics of Equalization 3  
Likewise, if the lowest gain setting of any band in this same Edit  
Group is -4 dB, then the largest number you will see in the Relative  
Gain display going all the way up is 16 (see fig. 5).  
So if you run the Relative Gain display up and down repeatedly  
with this Edit Group, the display will hit the "ceiling" at 16 and  
bottom out at 18.  
The Release Edit Group function  
Once you have changed the value of the Edit Group, the DEQ230  
will react one of two ways to further presses of the [BAND  
SELECT] buttons. To decide which option suits your working  
method or circumstance, experiment with the setting for the  
Release Edit Group function in Setup Mode.  
If this function is on, the very next [BAND SELECT] button  
you press after you have changed the level of the Edit Group will  
"release" all of the previously selected bands. The only band that  
will be selected is the one you just pressed. You will know this  
when it happens, because that's the only Band Gain LED that will  
be blinking.  
If the Release Edit Group function is off, the next [BAND  
SELECT] button you press after you have changed the level of  
the Edit Group will simply add that band to the Edit Group.  
Remember, if you want to  
keep the edited program,  
be sure to store it to one of  
the User locations. For  
instructions on how to do  
this, turn to page 38.  
For a more detailed explanation of the Release Edit Group  
function, see pages 44 and 45.  
 
37  
3 Basics of Equalization  
Basic operation: Store mode  
Once you have created a program you would like to save, press the  
[STORE] button to enter Store mode. This will cause the  
Numeric LED Display to blink with the number of the current  
program.  
If you were on a Preset program while editing, you will not be able  
to store the program until you select one of the 30 User program  
locations as its destination. To do this, use the [DOWN/UP]  
buttons. If you press the [UP] button first, you will see the  
Numeric LED Display jump to User program 30, which is the first  
available User program location. If you press the [DOWN]  
button first, you will see the Numeric LED Display jump to User  
program 59, which is the highest-numbered User program location  
available. If you were already on a User program when you entered  
Store mode, then using the [DOWN/UP] buttons will call up the  
next User program.  
Once you are in the User program area inside Store mode, pressing  
the [DOWN/UP] buttons allows you to choose a program  
number between 30-59 as the destination for your edited program.  
Pressing and holding one of these buttons will cause the unit to  
scroll progressively faster through the available choices. If you're  
holding the [DOWN] button, when the unit reaches User  
program 30 it will "wrap" around to number 59 and continue  
scrolling downward. Pressing and holding the [UP] button will  
cause the numbers to scroll in the opposite direction, wrapping  
from program 59 to program 30 and continuing upward.  
As in Program mode, there's an even faster way to select the  
destination program location. If you press and hold the [DOWN]  
button and then push the [UP] button, the unit will jump to  
Program 30. If you continue pressing the [UP] button, the  
DEQ230 will jump forward through the User locations in  
increments of 10 (40, 50, 30, 40, 50, etc.). Similarly, if you press  
and hold the [UP] button and then push the [DOWN] button,  
the unit will jump to Program 30. If you continue pressing the  
[DOWN] button, the DEQ230 will jump backward through the  
User locations in increments of 10 (50, 40, 30, 50, 40, 30, etc.).  
Once you have chosen the location you want, press the [STORE]  
button again. This will store the program into the user location  
you selected.  
Remember, if at any time you decide you do not want to save the  
edited program, simply press the [LINK/EXIT] button to return  
to Program mode. Your edited program will still be there, as  
evidenced by the dot on the right side of the Numeric LED  
Display. The “destination” program will not have been  
overwritten.  
 
38  
Basics of Equalization 3  
Channel Copy  
You can use the Link function while editing to help set up identical  
curves on both channels. But at some point the curves may need  
to diverge slightly (or significantly). Rather than unlinking the  
channels and starting all over again on Channel B, we have  
included a handy feature called Channel Copy as a subset of Store  
mode.  
The Channel Copy feature is a real time-saver. It will allow the  
settings from Channel A to be stored over whatever settings are in  
Channel B, so that after the completion of the Store process there  
will be no difference between the settings of Channels A and B for  
that program. Then you can begin to diversify the settings of the  
channels to match the needs of the incoming audio.  
The process is simple, but it is subtly different from the normal  
Store procedure. Pay close attention to the following steps:  
1. Before storing the program, unlink the channels. That way  
you’ll be able to begin editing Channels A and B  
independently as soon as you complete step 7.  
2. Press and hold the [STORE] button to enter Store mode. The  
Numeric LED Display will begin to flash.  
3. While holding the [STORE] button, press the  
[LINK/EXIT] button. This will cause the Link LED to  
begin flashing also.  
4. Release both buttons.  
5. Select the location for the new program using the methods  
described on the previous page.  
6. To abort the Store procedure, press the [LINK/EXIT]  
button. The settings for Channel A will not have been copied  
over to Channel B.  
7. To store the program, press the [STORE] button a second  
time. The settings for Channel A will have been duplicated on  
Channel B. To confirm this, toggle the [LINK/EXIT]  
button. You should see no difference between the settings of  
the channels. Even the Channel Level settings of Channel B  
should match that of Channel A.  
 
39  
3 Basics of Equalization  
Basic operation: Audition mode  
No doubt there will be times when you want to switch back and  
forth between different programs to determine which one is best  
suited for the audio source. But as easy as it is to navigate between  
the DEQ230's programs in Program mode, it's still difficult to  
focus on what's happening to the audio when you're making sure  
you land on the right program.  
Audition mode provides the solution. It allows you to specify any  
of the 60 programs within the DEQ230 as members of the  
Audition List. This is like a series of bookmarks, allowing you  
to jump over programs that are not intended for a particular  
audio source and only call up the ones that are.  
Be sure to store any edits you  
want to keep prior to entering  
Audition mode. The Audition  
list only uses Preset programs  
or programs that have been  
stored to the User locations.  
To enter Audition mode, first be sure the DEQ230 is in Program  
mode. After that, press and hold the [LINK/EXIT] button and  
then press the [DOWN] button. You will see four more LEDs  
light up over one of the [BAND SELECT] buttons, in addition  
to the Band Gain LEDs that were already lit for the current  
program. These four LEDs indicate that the [BAND SELECT]  
button beneath them now represents the active program in the  
Audition List. You will also see the number of the active program  
in the Numeric LED Display.  
The [BYPASS] button is also  
available in Audition mode.  
You can use it to “audition”  
the original signal manually,  
or you can use program 00  
“Flat” in the Audition list to  
automate theDEQ230’s  
return to the unprocessed  
audio signal.  
As you know, the DEQ230 has 60 programs. Conveniently, it also  
has 60 [BAND SELECT] buttons. So in Audition mode the  
[BAND SELECT] buttons represent a "map" of the Preset and  
User programs, and are used to select the programs that will be  
auditioned.  
For example, if you entered Audition mode while you were on  
Preset program 04, then the stack of lit LEDs would be above the  
63 Hz band on Channel A. If you want to toggle between that  
program and Preset program 10, count six [BAND SELECT]  
buttons to the right and press the 250 Hz button. You will notice  
that now there are four LEDs lit above the 250 Hz [BAND  
SELECT] button and only two LEDs lit above the 63 Hz band.  
As you recall, the four LEDs indicate which of the programs is  
active. The presence of two lit LEDs indicates that a program is  
part of the Audition List, but is not currently the active program.  
Remember, the very first  
program is program 00. So if  
you want to include program  
01 in the Audition list, you will  
need to select the second  
[BAND SELECT] button from  
the left. This is because  
program 01 is the second  
program in the DEQ230’s  
memory.  
You may add as many programs as you like to the Audition List. If  
you no longer want a given program to be part of the Audition  
List, simply press its [BAND SELECT] button again briefly. Its  
LED will turn off, indicating that this program will be skipped  
over the next time you cycle through the Audition List.  
If you can’t remember what  
factory curves correspond to  
each program number, refer to  
the Program Charts in  
Chapter 5.  
To exit Audition mode, press the [LINK/EXIT] button again, or  
deselect all programs from the Audition List.  
 
40  
Basics of Equalization 3  
Audition Automation  
There are two ways to toggle between the programs in the  
Audition List: manually and automatically. The DEQ230 defaults  
to the automatic method, which we call Audition Automation.  
Once you have finished adding programs to the Audition List, the  
DEQ230 begins cycling through the programs from left to right. It  
will start with the currently active program, pause for several  
seconds, and move on to the next. When it reaches the last  
program in the Audition List, it will start over again from the first  
one on the left. Remember that the stack of four LEDs will  
indicate which program is currently the active one. Also note that  
you can edit the Audition List by adding or removing programs  
during the Audition Automation cycle.  
When changing the time  
value for the Audition  
Automation, keep in mind  
that the choices “wrap”;  
i.e., you can reach a value  
of 25 from a value of 01  
with a single press of the  
[DOWN] button.  
It’s possible to shorten or lengthen the amount of time spent on  
each program in the Audition List during Audition Automation.  
Use the [DOWN/UP] buttons for this purpose. The time range  
is from 1-25 seconds in increments of one second. You will see  
the value briefly in the Numeric LED Display as you change it,  
and then the display will resume showing the number of the  
current program in the Audition List. The Audition Automation  
time value you select will be remembered even after turning the  
DEQ230 off and on again.  
Audition Automation override  
If you want to hear a certain program again without having to wait  
for the DEQ230 to cycle through the entire Audition List, simply  
press and hold that program's [BAND SELECT] button. This  
will call up that program immediately. And as long as you hold  
down that [BAND SELECT] button, the DEQ230 will suspend  
the Audition Automation cycle and stay on that program. Once  
you release the button, the next program in the Audition List will  
be called up and the cycle will continue from there.  
If you want to audition  
programs in a specific  
order, save them to  
locations in the User area  
(programs 30-59) in the  
order you’d like to hear  
them. Then select them in  
Audition mode.  
Manual Audition  
If you prefer to call up each program in the Audition List at your  
own pace, then you must turn off the Audition Automation  
feature. To do this, you will need to enter Setup mode and toggle  
the setting for the AUD AUTO function. For information on how  
to do this, see page 46.  
Once you have turned off the Audition Automation feature,  
navigation through the Audition List is handled by the  
[DOWN/UP] buttons. Pressing the [DOWN] button will move  
you leftward through the Audition List, and pressing the [UP]  
button will move you rightward through the list. If you have a lot  
of programs in the Audition List, hold down one of those buttons  
and after a couple of seconds the DEQ230 will begin to scroll  
through them more quickly.  
 
41  
3 Basics of Equalization  
Basic operation: Channel Level mode  
Channel Level mode allows you to adjust the output level of  
channels A and B independently or simultaneously. Use this  
feature to compensate for a reduction or increase of signal level  
due to the equalization curve you have selected.  
To enter this mode you must start from Program mode. Once you  
are there, you can enter Channel Level mode in one of two ways:  
On Channel A, press and hold the 16 kHz button and then  
press the 20 kHz button, or vice versa  
Once you are in Channel Level  
mode, you must press both of  
the appropriate Band Gain  
buttons on one or the other  
side of the Numeric LED  
Display in order to select or  
deselect one of the channels. If  
you press only one Band Gain  
button, the channel selection  
will not change.  
On Channel B, press and hold the 25 Hz button and then  
press the 31.5 Hz button, or vice versa. (This option only  
works when the channels are not linked.)  
Note: If you press only one Band Gain button, you won't  
enter Channel Level mode--you may have entered Band Edit  
mode by mistake.  
Once the DEQ230 is in Channel Level mode, you will see the  
Band Gain LEDs go completely dark except for the ones over the  
buttons mentioned in the two steps above.  
From this point onward, Channel Level mode operates exactly like  
Band Edit mode: the settings for Release Edit Group and Edit  
Time Out are in effect; if you select both channels A and B for  
editing, you have selected an Edit Group; the Relative Gain  
Display and Proportional Gain Memory will govern the gain  
adjustments made to the Edit Group.  
For information on selecting  
an Edit Group, see page 34.  
For information on the  
Release Edit Group function,  
see page 45. For information  
on the Edit Time Out feature,  
see page 46. For information  
on the Relative Gain Display,  
see page 34. For information  
on Proportional Gain  
The only real difference between the way this mode and Edit  
mode operate is in the amount of boost that is allowed to occur in  
Channel Level mode. The DEQ230 will allow each channel to be  
boosted up to +6 dB, with an allowable cut range of -12 dB. If  
you want another 6 dB of gain (for a total of 12 dB), you will find  
that in the Master Level function in Setup mode. But remember,  
the settings for Channel Level mode are stored with each program.  
The settings for the Master Level function are not.  
Memory, see page 34.  
To exit Channel Level mode and return to Program mode, deselect  
both channels or press the [LINK/EXIT] button.  
If the Numeric LED Display  
shows “Li,” when you press  
[BAND SELECT] buttons on  
Channel B, it means the  
channels are linked. Either  
make the edits on Channel A,  
or return to Program mode  
and press [LINK/EXIT] to  
unlink the channels.  
 
42  
Basics of Equalization 3  
The "Hidden" Modes  
There are several sub-levels of operation that can be accessed  
from Program mode by pressing different buttons. We covered  
Channel Level mode and Audition mode on the preceding pages;  
here are two more “hidden” modes:  
Demonstration mode  
Being in Demonstration mode  
is something like being in  
Audition mode; the DEQ230  
will cycle automatically  
through all 60 programs one  
after the other. The main  
difference is that while in  
Demonstration mode, the  
audio signal is bypassed.  
Sometimes it’s fun to have a lot of little lights flashing from the  
stage or in the studio. The DEQ230 has a special key combination  
that will activate a “light show” for the entertainment of your  
clients, audience, or children. To begin the pyrotechnics, first make  
sure you are in Program mode. Once you are, hold down the  
[LINK/EXIT] button and press the [UP] button.  
To exit Demonstration mode, press the [LINK/EXIT] button.  
Real-time Analysis mode (DEQ230D only):  
The DEQ230D is capable of another “light show” that is even  
more useful than it is entertaining. Real-time analysis (RTA) mode  
uses the Band Gain LEDs to show you exactly which frequencies  
are present in the audio signal that is passing through the  
DEQ230D. This is an extremely useful tool that has been a  
mainstay of serious sound reinforcement engineers for decades.  
To enter RTA mode, press the two leftmost [BAND SELECT]  
buttons on Channel A (25 Hz and 31 Hz). Immediately, the  
DEQ230D will start giving you visual feedback as to what is going  
on with the instrument or mix that is being processed. RTA mode  
monitors the outputs of the DEQ230D, so when you press the  
[BYPASS] button you will be seeing what you are hearing: the  
unprocessed signal.  
There are two ways to get out  
of RTA mode: pressing the  
25 Hz and 31.5Hz buttons on  
Channel A simultaneously, or  
by pressing the [LINK/EXIT]  
button.  
Metering modes  
Like any professional audio product, the DEQ230D allows you to  
configure the response of the Band Gain LEDs while in RTA  
mode. Use the [DOWN] and [UP] buttons to select between the  
four different settings:  
Held peaks may be reset at  
any time by pressing the  
[DOWN] and [UP] buttons  
simultaneously.  
00  
01  
Peaks are not held.  
Peaks are held for one second.  
02  
Peaks are held for two seconds.  
OO  
Peaks are held until the metering mode is switched  
to another setting, or until you exit RTA mode.  
If you want to reset the peaks while they are being held in  
Momentary 1, Momentary 2, or Continuous settings, press the  
[DOWN] and [UP] buttons at the same time.  
 
43  
3 Basics of Equalization  
Setup mode  
This is where you will find some of the features that govern the  
way the DEQ230 operates in the other modes. They are what you  
would call "Global" settings, in that their status is not stored with a  
program. No matter which program you call up, these settings will  
not change. And since they make such a big difference in how the  
unit works, they have been "tucked away" so they won’t be altered  
accidentally.  
To access Setup mode, first you must turn off the DEQ230. Then  
turn the unit back on, wait until you see the letters “DEQ230” in  
the display, and then hold down the [STORE] button. After a  
couple of seconds you will see the word "SETUP" appear in large  
letters above Channel A‘s [BAND SELECT] buttons. Then the  
LEDs over Channel A will read "M. LVL," and the LEDs over  
Channel B will read "+00."  
To return to Program mode  
from Setup mode, press the  
[LINK/EXIT] button or turn  
the DEQ230 off and back on.  
The first twelve [BAND SELECT] buttons of Channel A are  
used to select between the different functions in Setup mode. They  
are:  
Item (button) Function  
Displayed  
Options  
Default  
Value  
1 (25 Hz)  
2 (31.5 Hz)  
3 (40 Hz)  
4 (50 Hz)  
5 (63 Hz)  
Master Level  
Release Edit Group  
Audition Auto  
Edit Time Out  
Lock  
M. LVL  
+/- 6 dB  
Off/On  
Off/On  
Off/On  
Off/On  
0 dB  
REL E.G.  
AUD AUTO  
EDIT T.O.  
LOCK  
On  
On  
Off  
Off  
The following functions are available on the DEQ230D only.  
6 (80 Hz)  
MIDI Channel  
MIDI CH  
PRG CHG  
SND SYX  
All, 1-16  
Off/On  
ALL  
On  
7 (100 Hz)  
8 (125 Hz)  
9 (160 Hz)  
10 (200 Hz)  
11 (250 Hz)  
12 (315 Hz)  
MIDI Program Chg  
Sys-Ex Transmit  
Sys-Ex Receive  
Send?  
N/A  
N/A  
Thru  
48  
RCV SYX  
Waiting  
Out/Thru  
44.1/48  
MIDI Out/Thru Select  
Sample Rate Select  
Force Analog Input  
MIDI O/T  
INT CLOCK  
INPUT SRC  
Auto/Analog  
Auto  
The [STORE] button may be  
used to cycle through the  
functions also.  
Note that as you switch from one function to the next that the  
Numeric LED Display will change to show the number of the  
selected function.  
 
44  
Basics of Equalization 3  
Here's a description of what each function does.  
Button 1: Master Level (+/- 6 dB)  
The Master Level function is one way to customize the DEQ230  
to your environment. If the equipment in your setup tends to send  
very hot signals, you can use this function to prevent the output of  
the DEQ230 from clipping.  
When a hot line level signal comes in, the DEQ230 has plenty of  
headroom to deal with it. But if you perform some radical  
equalization on this signal, it is possible that the combination of  
the incoming hot signal plus the equalization you have done may  
put the signal "over the top" and within range of clipping. The  
Master Level function allows you to reduce the level of the  
equalized signal before it reaches the final output stage of the  
DEQ230.  
Don't confuse this with the Channel Level settings in Edit mode.  
The Channel Level settings are stored with the program, and  
therefore may vary from program to program. The Master Level  
setting is global; i.e., it is always active and will affect every  
program. There is a diagram on page 30 that illustrates the  
relationship between Channel Level and Master Level.  
To lower or raise the Master Level setting, use the [DOWN/UP]  
buttons. To reset the value of this function to 0 dB, press the  
[DOWN] and [UP] buttons at the same time.  
For an explanation of how to use the Channel Level control  
feature, see page 42.  
Button 2: Release Edit Group (On/Off)  
Of all the Setup features, this is the one that will most affect the  
way you work with the DEQ230. The Release Edit Group setting  
determines the behavior of the [BAND SELECT] buttons in  
Edit mode.  
If you are likely to edit only  
one or two bands at a time  
when constructing a new  
curve, set the Release Edit  
Group function to On. This  
will enable you to move  
more quickly across the  
audio spectrum.  
For the sake of describing this feature, let's review some things we  
already know. When you press a [BAND SELECT] button, you  
enter Edit mode. If you don't press one of the [DOWN/UP]  
buttons right away, you can keep pressing [BAND SELECT]  
buttons until you have several of them selected simultaneously.  
This is called selecting an Edit Group.  
Once you have selected an Edit Group, you can cut or boost the  
gain of all of the bands in the Edit Group simultaneously; they  
will move up or down in proportion to one another. The Release  
Edit Group feature does not affect these things; this is always how  
the DEQ230 operates.  
However, once you make an edit, it makes a big difference whether  
the Release Edit Group feature is on or off. If it is on, the very  
next [BAND SELECT] button you press will "release" all of the  
previously selected bands. The only band that will be selected is  
the one you just pressed. You will know this when it happens,  
because that's the only Band Gain LED that will be blinking.  
 
45  
3 Basics of Equalization  
If the Release Edit Group feature is off, the next [BAND  
SELECT] button you press after you have changed the level of  
the Edit Group will simply add that band to the Edit Group. The  
upside of this is the convenience of being able to edit three  
frequencies +3 dB, for example, and then add another frequency  
to the pile and edit them all another +2 dB without having to  
reselect the first three. The downside is that you will have to  
deselect all four bands if you want to grab one more frequency  
and edit it by itself.  
There are pros and cons to both ways of working. So, experiment  
with this feature and see which way works best for you.  
To enable or disable the Release Edit Group feature from this  
Setup mode page, press one of the [DOWN/UP] buttons.  
Button 3: Audition Automation (On/Off)  
This setting determines whether or not the Audition Automation  
function is active. When it is, the DEQ230 will cycle automatically  
through the programs in the Audition List. When it is not, the user  
must cycle through the Audition List manually.  
To enable or disable this function, press one of the [DOWN/UP]  
buttons. For a more extensive explanation of how to use Audition  
mode, turn to page 40.  
Button 4: Edit Time Out (On/Off)  
The Edit Time Out function serves as an "auto-exit" feature.  
When it is enabled, if you have not changed the gain value of any  
band or Edit Group for 30 seconds, the DEQ230 will exit  
automatically to Program mode.  
We have included this feature so the DEQ230 can mold itself as  
seamlessly as possible into your working style. If you prefer not to  
have the unit continue reminding you it is still in Edit mode by  
blinking its LEDs, vying for your attention, as it were, with the VU  
meters on your mixer, then Edit Time Out is a feature you will  
appreciate.  
On the other hand, if you prefer to have the DEQ230 remain in  
Edit mode so you will not lose your chosen Edit Group when the  
unit returns to Program mode, you may want to turn the Edit  
Time Out function off.  
The default setting for this function is "Off;" to enable it press one  
of the [DOWN/UP] buttons.  
Button 5: Lock (On/Off)  
This function enables you to choose a particular program as the  
only one that can be selected once the DEQ230 is powered on.  
After this has been done, pressing any button besides the  
[POWER] button will cause the Numeric LED Display to show  
“Lo” for “locked.” This is handy for environments in which the  
DEQ230 is used for tuning a room, for example, or whenever you  
don't want someone calling up a different program, editing the  
 
46  
Basics of Equalization 3  
current program, and/or storing a different program on top of the  
one you have created for a particular application.  
Before you try this feature, make sure you're happy with the  
program you had selected prior to turning the unit off. It will be  
the program you are "stuck" with when you turn the unit back on  
after enabling the Lock feature.  
If you're already in Setup mode, all you have to do to enable this  
feature is press the fifth [BAND SELECT] button and then press  
one of the [DOWN/UP] buttons. You should see the LEDs over  
Channel B change from "OFF" to "ON." Then turn the unit off  
and on again. Your DEQ230 is now locked. (No fair using this  
knowledge to play tricks on your salesperson!)  
It's simple to restore the DEQ230 to full functionality (i.e.,  
"unlock" it). Just turn the unit off and power it up in Setup mode  
again (turn the unit on and then hold down the [STORE] button).  
Then press the fifth [BAND SELECT] button and press one of  
the [DOWN/UP] buttons to turn this feature off. The next time  
you power up the DEQ230 it will operate normally.  
Buttons 6-12 (DEQ230D only)  
Button 6: MIDI Channel (ALL, 1-16)  
The setting for this function determines which MIDI channel the  
DEQ230D will use to send and receive program changes. The  
ALL setting means program changes will be received regardless of  
which channel they are on. When ALL is selected, program  
changes will be sent only on channel 1.  
Remember, the functions for  
buttons 6 through 12 are only  
available on the DEQ230D.  
Use the [DOWN/UP] buttons to select the desired setting.  
Button 7: MIDI Program Change (On/Off)  
The default setting for the MIDI Program Change function is  
“On.” If you want the DEQ230D not to respond to program  
changes, use the [DOWN/UP] buttons to change it to “Off.”  
Button 8: System Exclusive Transmit (Send?)  
When on this page, pressing the [UP] button will cause the  
DEQ230 to transmit all 30 of its User programs over the MIDI  
Out jack in “system exclusive” (sys-ex) format. This is a great way  
to back up your hard-fought programs, and the combination of  
this function and the next makes it easy to configure the  
DEQ230D for particular settings.  
Once the transmission has begun, you will see a brief message of  
“Sending,” followed by the message “Done.” Shortly after that, the  
DEQ230D will return to the original message “Send?”  
This process is not affected by the setting of the MIDI Out/Thru  
Select function (Button 10). When you instruct the unit to  
Transmit, the sys-ex data will be sent whether the MIDI jack is set  
to Out or Thru.  
 
47  
3 Basics of Equalization  
Button 9: System Exclusive Receive (Waiting)  
As long as this page is active, the DEQ230D will allow an external  
device such as a computer to transmit a new bank of 30 User  
programs into its User memory space. Once the external device  
begins sending the proper sys-ex data, the DEQ230D displays  
the message “Rcving,” or “receiving.” Depending on the speed  
of the transmission, the transfer can happen so quickly you may  
not see that message. Either way, when the sys-ex transmission is  
complete, the DEQ230D will let you know by displaying the  
message “Done.”  
Warning! Sending a  
sys-ex bank into the  
DEQ230D will overwrite  
the User memory  
locations. Make sure  
you have backed up the  
entire User memory  
before you load in a new  
set of User programs.  
If you change your mind in the middle of the transmission and  
realize you’ve loaded in the wrong bank (or worse, you forgot to  
back up the User programs first), you can interrupt the  
transmission by pressing the [DOWN] button. But you’d better  
act quickly, as the whole process takes only about one second.  
And unfortunately, as soon the message “Rcving” is displayed the  
DEQ230D begins overwriting programs in the User bank. If you  
saw that message you will have lost some User programs. But if  
you interrupted the transmission, you will have managed to save  
some of the programs.  
Button 10: MIDI Out/Thru Select (Out/Thru)  
Sometimes it is necessary to “daisy-chain” MIDI devices so the  
MIDI data from one unit will be passed through one or more  
other pieces of MIDI gear until it is able to reach the last unit in  
the chain. The DEQ230D will allow you to do that when this  
function is set to Thru (the default value).  
The setting on this page will not affect whether or not the  
DEQ230D will send its memory out the MIDI Out jack. When  
that command is initiated (Button 8), the sys-ex data will be sent in  
either case.  
Button 11: Sample Rate Select (44.1/48)  
The DEQ230D automatically senses an incoming digital signal  
through its S/PDIF input and slaves its internal clock to that,  
whether the rate is 44.1k or 48k. But if you need the DEQ230D to  
serve as an A/D converter, then it also will need to be the master  
clock to the receiving device.  
You may prefer to record the output of the DEQ230D at either  
44.1k or 48k. Use the setting of this function to set the internal  
clock to the desired sample rate.  
Button 12: Force Analog Input (Auto/Analog)  
There may be times when you want the DEQ230D to ignore an  
incoming digital signal, but you don’t want to have to reach around  
to the back of the rack and unplug the cable going into the  
S/PDIF input. This function will help prevent that tangled  
spaghetti-mess of cables where no one knows whether the other  
end is actually hooked up to anything!  
 
48  
Basics of Equalization 3  
Auto” is the default value. To force the DEQ230D to listen only  
to the balanced inputs, switch this setting from Auto to Analog.  
Button combinations  
Here is a list of the combinations of buttons that are possible in  
the DEQ230 and what they do:  
Hold:  
Press:  
Result  
[UP] (First press)  
[UP] (2+ presses)  
[DOWN] (First press)  
[DOWN] (2+ presses)  
[DOWN]  
Resets value  
Jumps value  
Resets value  
Jumps value  
Audition mode  
Demo mode  
Channel Copy  
[DOWN]  
[UP]  
[LINK/EXIT]  
[UP]  
[STORE]  
[LINK/EXIT]  
16 k (Ch. A)  
25 Hz (Ch. B)  
25 Hz (Ch. A)  
20 k (Ch. A)  
Channel Level  
31.5 Hz (Ch. B)  
31.5 Hz (Ch. A)  
RTA mode  
(DEQ230D  
only)  
“Power up” button combinations  
Press & Release  
Press:  
Result:  
[STORE]  
Setup mode  
Reinitialize  
Power  
[DOWN/UP]  
 
49  
3 Basics of Equalization  
Equalization Artifacts  
When you apply a lot of EQ (6dB or more), you may hear some  
consequences on the output. Here are a few common side effects  
to applying a lot of equalization and some ways to avoid them.  
The potential for artifacts is  
highly dependent on the audio  
source material. A DEQ230  
program that works well for  
processing one source may  
clip when processing another  
source, depending on which  
frequencies are present.  
Making the program work may  
be simply a matter of a slight  
adjustment in the gain setting  
for one or two bands.  
Distortion  
If you boost too many frequencies too high, you will distort the  
output. If this happens, the red CLIP LED will light. To avoid  
this, turn down the signal being sent to the DEQ230. Other  
options include adjusting the Channel Level settings in Edit mode,  
or adjusting the Master Level setting in Setup mode. The best  
option is to try another method of achieving the desired effect: cut  
the highs instead of boosting the low frequencies; reduce the lows  
and highs instead of boosting the midrange, etc.  
Noise  
If you boost the high frequencies enough you may hear noise in  
your system that was inaudible otherwise. If this is objectionable,  
you may want to gate that channel when it isn’t being used or  
automate the console so that channel is muted when that  
instrument isn’t playing.  
Instruments usually sound  
better when you cut the  
problem frequencies instead of  
boosting the frequencies you  
want to feature.  
Phasing  
You may hear some phase distortion if you apply a lot of EQ,  
such as boosting 12dB on several bands, for example. This is just  
the nature of EQ –the more you cut or boost, the more phase  
distortion will occur. Try getting the same effect with less EQ; try  
cutting instead of boosting; try a different position for the  
microphone. All of these suggestions can help you to achieve the  
desired effect with minimal phase distortion.  
 
50  
Basics of Equalization 3  
Constant Q vs. Variable Q  
What makes the DEQ230 unique?  
At their inception, graphic equalizers relied solely on a form of  
equalization known as "Variable Q." The DEQ230, on the other  
hand, is what is known as a "Constant Q" equalizer. This method  
of equalization is a relatively recent development in the history of  
sound reinforcement and recording technology. As you will see  
illustrated in the charts in this section, the Constant Q method  
allows for a higher degree of control over the sound being  
processed because of its significantly greater accuracy.  
Before we go any further, it's time for some definitions:  
Q
The range of frequencies affected by a  
band  
Variable Q  
A process in which the range of  
frequencies affected by a band changes as the  
amount of gain is cut/boosted  
Constant Q  
A process in which the range of  
Frequencies affected by a band stays the  
same as the amount of gain is  
cut/boosted  
It may help to define these terms visually as well.  
In the following illustration, we see the three basic terms that  
govern the operation of a single band. The vertical bar of the  
graph represents decibels of cut/boost, and the horizontal bar  
represents frequency in Hz. The dotted line leading to the center  
of the curve indicates the frequency at which this band is set. You  
can see that in this example, Q covers a range of frequencies from  
about 200 Hz to about 5 KHz.  
 
51  
3 Basics of Equalization  
In the next illustration, the difference between a narrow Q and a  
wide Q is seen:  
Variable Q  
Now we're ready for a visual definition of the term Variable Q. In  
the next illustration, the wider and more gradual curve represents a  
lower gain setting for a variable Q equalizer. The narrower and  
more steep curve represents a higher gain setting at the same  
frequency:  
The previous illustration has been exaggerated somewhat to make  
the point, but you can see how a lower gain setting also boosts  
frequencies that overlap to some extent into the regions affected  
by the next highest and lowest frequency band controls.  
Constant Q  
In contrast, a Constant Q equalizer has a more consistent range of  
frequencies under its control throughout its cut/boost range, as  
illustrated below:  
 
52  
Basics of Equalization 3  
Multi-band application and results  
So far we have only dealt with cutting or boosting single frequency  
bands. The differences between the constant Q and variable Q  
methods become more "graphic," if you will, when adjacent  
frequency bands are involved.  
In this example, three adjacent bands are used. They have settings  
of + 6 dB, 0 dB, and + 6 dB, respectively:  
You can see how the 0 dB setting on the variable Q equalizer  
merely serves to round off the top of the curve; in actuality, this  
translates into a boost in the range of frequencies under that  
band's control. You would have to cut the gain on that band  
significantly to reduce the unintended consequences of boosting  
the other two frequency ranges.  
The constant Q equalizer, on the other hand, has more precise  
control over each of the frequency bands. As you can see in this  
example, the effect on the center band is significantly lower:  
 
53  
3 Basics of Equalization  
To further illustrate the differences, here is a pair of examples in  
which three adjacent bands have settings of + 3 dB, -3 dB, and + 3  
dB, respectively:  
Remember that at lower gain settings, there is an even wider Q for  
a given frequency band on a variable Q equalizer. The center  
frequency band needs to be edited even more drastically in order  
for any noticeable reduction of frequencies in its range.  
The corresponding illustration for the constant Q equalizer speaks  
for itself:  
We offer this information regarding the differences between  
constant Q and variable Q equalizers not as an attempt to  
persuade the world to reject variable Q equalizers out of hand; in  
some applications either would do the job nicely. But when a  
greater degree of control over the program material is needed, a  
constant Q equalizer like the DEQ230 offers a significant  
advantage.  
 
54  
4 Applications  
This section is designed to get you started with the DEQ230 by  
giving some sample settings. These are merely suggested settings;  
experiment and find your own once you begin to hear what the  
DEQ230 does to your sound.  
In a way, it’s absurd to suggest EQ settings without knowing what  
the source sounds like. EQ is a tool that’s used to change the  
timbre of a sound, and it’s impossible to suggest an EQ setting  
that, for example, will make all guitars sound better. So the goal of  
this section is to give you some ideas for using EQ on your own  
tracks.  
Rock Kick Drum  
A rock and roll kick drum is usually EQ’d quite a bit to make it  
sound the way it does on the radio. Usually an engineer will choose  
to cut some of the woofy low-midrange, while boosting the high-  
end "slap" and maybe even some of the lows. Here is a setting to  
try on a close-miked kick drum:  
Select all frequencies below 80Hz and boost 3dB  
Cut 500Hz by 8dB  
Boost all frequencies above 5kHz by 4dB  
You may also want to apply some compression and gating with the  
Alesis CLX-440.  
Vocal Air  
A popular effect on vocals is to boost the high frequencies to add  
"air" to the vocal. This is an especially popular effect on ballads  
sung by R&B divas. This effect is achieved by boosting the high  
frequencies:  
Boost 16 kHz by 6dB  
Boost 20 kHz by 6dB  
Tape Hiss Removal  
If a recording has a lot of tape hiss, such as one transferred from  
cassette, you can usually get rid of it by dropping the high  
frequencies a bit:  
Select all frequencies from 8kHz up and cut them by 6dB  
Adjust the gain of different bands to compromise between  
keeping the high end of the recording and eliminating tape hiss.  
 
55  
4 Applications  
Eliminating Feedback  
During a live performance, you may experience feedback if a  
microphone is placed too close to a monitor. However, this  
feedback often occurs at one frequency before it happens at  
others. You can "ring out" the monitor by using EQ to cut the  
frequency that’s feeding back. The following is best to try when the  
band and audience are not present:  
This procedure can be an  
effective tool in isolating and  
eliminating feedback in the  
main or house system as well.  
1. Insert the EQ between the mixer’s monitor output and the  
monitor amplifier.  
2. Slowly and carefully raise the monitor level to the point of  
feedback. Notice that it always feeds back at the same  
frequency unless the mic is moved a lot. As soon as you hear  
feedback, turn the monitor level down, but not off.  
3. Select a band that is near where you think the feedback is  
occurring. For example, if you’re getting high-frequency  
feedback, try 6.3 kHz.  
4. Slowly raise the 6.3 kHz Band Gain level while listening for  
feedback. If you hear feedback, cut that frequency because you  
guessed right.  
5. If you don’t hear feedback, return that band to “0” and repeat  
this procedure with another frequency band. Once you hear  
feedback, cut that frequency.  
If you don’t hear feedback at any frequency using this method, try  
boosting the monitor level a little more.  
Filtering effects  
The answering machine  
A popular vocal effect is to filter the voice to a limited frequency  
range. This “telephone” effect is also called “futzing,” and can be  
used on any instrument or mix. Here’s how to get that sound on  
the DEQ230:  
If the Numeric LED Display  
shows “Li” when you press  
[BAND SELECT] buttons on  
Channel B, it means the  
channels are linked. Either  
make the edits on Channel A, or  
return to Program mode and  
press [LINK/EXIT] to unlink  
the channels.  
1. Follow the instructions for items 1 and 2 from Step 2.  
2. Press all of the [BAND SELECT] buttons in the ranges  
from 25 Hz to 630 Hz and from 6.3 kHz to 20 kHz on the  
channel you are using.  
3. Use the [DOWN] BUTTON to reduce all of these  
frequencies until their LEDs are at -12 dB.  
4. Select all of the unedited frequencies and boost them as high  
as you can without clipping the signal.  
5. Be sure to toggle the [BYPASS] button to compare the result  
with the original.  
 
56  
Applications 4  
Comb filtering  
You'll understand how this effect process got its name once you  
see the way it looks when recreated on the DEQ230:  
1. Follow the instructions for items 1 and 2 from Step 2.  
2. Starting from the far left of Channel A, press every other  
[BAND SELECT] button and take those bands all the way  
down to -12 dB. Then select the unedited bands and boost  
them +6 dB. When you’re done, look at the LEDs on the  
DEQ230 and remember the “comb” analogy. The bands set to  
+6 dB are the “teeth” of the comb, and those set to –12 dB  
are the spaces between the teeth.  
Note: depending on the  
incoming audio, it may be  
necessary to reduce the gain  
on some bands to prevent  
clipping.  
3. For an even more interesting effect, press the [LINK/EXIT]  
button to unlink the bands on Channel B from Channel A and  
create the exact opposite settings. In other words, take the  
“odd” bands on Channel B to +6 dB this time and the “even”  
bands to –12 dB. Be sure to toggle the [BYPASS] and  
[LINK/EXIT] buttons to get an idea of what is being done  
to the signal as it passes through the DEQ230.  
There are preset programs  
similar to the ones used in  
these examples. You may find  
it interesting to compare the  
results of the different settings  
used in program 08 ("Comb  
filter - 125 Hz") and program  
14 ("Telephone").  
4. Experiment with different sized "teeth" and "spaces." Put two  
adjacent frequencies down and the next one up, repeating the  
pattern. Try "broken" teeth (i.e., boosting some frequencies  
more than others)! Adjust which frequencies to emphasize/de-  
emphasize to suit the incoming audio.  
 
57  
4 Applications  
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58  
5 Program Charts  
Note for all program charts  
An "L" in the middle of the picture of the front panel indicates that a program’s LINK  
function is active.  
#
Title  
Description  
0
Flat  
The DEQ230 will not affect the signal; the output signal will  
sound the same as the input signal.  
1
Smile  
The smile curve is a time-tested technique used by live sound  
engineers. No time for a sound check? Start here.  
2
3
4
5
Brighten  
Warmth  
Darken  
Speech  
If you need to give your sound a little sharpness to cut through...  
Soften the edginess of your mix with this program.  
This is for the times when subtlety isn't enough.  
This eliminates unexpected rumbling or mic handling noise and  
lends some clarity to the upper end.  
 
59  
5 Program Charts  
6
Loudness Plus  
This curve approximates what happens when you press the  
“Boost” button on some consumer-level stereo equipment. It  
makes for a nicely balanced sound when listening at low levels.  
7
8
9
Techno  
This setting emphasizes the extremes to get the dancing bodies  
really moving.  
Comb Filter - 125 Hz  
Feed a signal into it that contains 125 Hz and it will really  
emphasize that frequency.  
A: Kick  
Link=Off. Feed Ch. A a kick drum for thump, beater tap, and to  
reduce hollowness. Ch. B reduces low end to separate the snare  
and kick and also reduces hollowness.  
B: Snare  
A: Bass Guitar  
10  
11  
Link=Off. Gets you in the ballpark for bass and guitar, but your  
results may vary--make adjustments as needed.  
B: Acoustic Guitar  
A: Male Vocal  
These generally fit the physics of male and female voices. The  
low end is reduced to avoid unwanted rumble and the high end is  
emphasized for increased intelligibility.  
B: Female Vocal  
 
60  
Program Charts 5  
12  
Cross-Over  
Split a full-range mono signal into both channels; send the output  
of Channel A to an amplifier feeding the woofers and send  
Channel B to an amplifier feeding the tweeters.  
13  
Hum Reduction  
Some signals have 60Hz hum no matter what you do. This  
program de-emphasizes 60Hz and its harmonics without taking a  
noticeable bite out of the sound.  
14  
15  
Telephone  
Use this as an effect to simulate what signals sound like passing  
through the phone.  
Less SSS  
This program reduces sibilance--the sound when vocals' "S"  
sounds are out of proportion to other phonetics.  
Note for programs 16-20 and 22-26  
Send the signal you want to equalize through Narrow Boosts 1-5 to find the frequency that  
may be most objectionable. Take note of that frequency for further editing or just set the  
DEQ230 to the Narrow Cut 1-5 program that matches the Boost program that emphasized  
the frequency range in question.  
16  
17  
Narrow Boost 1 (80Hz)  
Narrow Boost 2 (250Hz)  
See note for programs 16-20 and 22-26  
See note for programs 16-20 and 22-26  
 
61  
5 Program Charts  
18  
19  
20  
21  
Narrow Boost 3 (800Hz)  
Narrow Boost 4 (2.5kHz)  
Narrow Boost 5 (8kHz)  
Low Shelf  
See note for programs 16-20 and 22-26  
See note for programs 16-20 and 22-26  
See note for programs 16-20 and 22-26  
Use this to eliminate the low rumble and leave everything else  
untouched (corner frequency is approximately 75Hz).  
22  
23  
24  
Narrow Cut 1 (80Hz)  
Narrow Cut 2 (250Hz)  
Narrow Cut 3 (800Hz)  
See note for programs 16-20 and 22-26  
See note for programs 16-20 and 22-26  
See note for programs 16-20 and 22-26  
 
62  
Program Charts 5  
25  
26  
27  
Narrow Cut 4 (2.5kHz)  
Narrow Cut 5 (8kHz)  
High Shelf  
See note for programs 16-20 and 22-26  
See note for programs 16-20 and 22-26  
Use this to eliminate the high end and leave everything else  
untouched (corner frequency is approximately 7kHz).  
28  
Sine Wave Pattern I  
Mostly for show, but because Channel A & B are not linked,  
there can be some happy accidents in terms of how these  
programs affect your signals.  
29  
Sine Wave Pattern II  
See note for program 28.  
Note for programs 30-59  
The following 30 programs reside in the User program area. They can be overwritten with  
your own programs. (Naturally, if you have done that, the following diagrams no longer  
apply.) We suggest that you try these before storing a new program in their place, though;  
you might find some of them useful as a starting point for some of your own programs. It is  
possible to recall all 30 of these at once (see page 71 for details). But be forewarned: doing  
so will erase any programs you have stored.  
30  
Vinyl Warmth  
This simulation mimics the frequency response of common  
phono players.  
 
63  
5 Program Charts  
31  
Tape Hiss Reduction  
This is a way to deal with noisy source material that originates  
from magnetic media.  
32  
Mini TV  
If you want to make your audio sound as if it’s coming from one  
of those portable televisions, try this one.  
33  
34  
35  
36  
Megaphone Bandlimit  
Sounds like what the name implies.  
Air Boost  
Just the opposite of the high shelf curve.  
AM Radio  
Another band-limiting curve for using as an effect.  
R&B Radio  
A simulation of the general emphasis of certain bass and treble  
frequencies found across modern R&B radio stations.  
37  
Acoustic Guitar Air  
Try putting two mics pointing at different areas of an acoustic  
guitar and running it through this program.  
 
64  
Program Charts 5  
38  
39  
40  
41  
Electric Guitar Bandlimit  
Rap Drums Hype  
Sizzle Cymbals  
Very often a really hot guitar track has to find a place in a  
crowded mix. This is one place to start looking for that special fit.  
If you've got a drum machine or drum mix that calls for woof  
and hot treble, send it through this curve.  
Reduce any live drum bleed-through and emphasize the cymbals'  
place at the high end of the mix.  
Cardboard Tube  
Remember when you were a kid and you had a friend speak to  
you through a cardboard tube?  
42  
43  
Bathtub  
Do you like the sound of singing in the shower?  
Mild Comb  
This is a variant on the comb-filter effect that is not as drastic as  
some of the other comb filter presets.  
44  
Resonance (125Hz)  
This setting is meant to emphasize 125Hz and all its harmonics  
such as 250Hz, 500Hz, 1kHz, 2kHz, etc.  
 
65  
5 Program Charts  
45  
11kHz Sample Rate  
If you want to digitize your signal at a very low sample rate like  
11kHz for effect, bandlimiting it to half the sample rate  
(approximately 5kHz) will help you avoid some nasty sounding  
artifacts of the sampling process.  
46  
Next Door Neighbor  
This is what it sounds like when there's a party going on next  
door.  
Note for programs 47-49  
These three following programs are for DJ's to squash the response of the music in order to  
create a temporary effect or to announce over.  
47  
48  
49  
50  
High DJ Isolation  
Mid DJ Isolation  
Low DJ Isolation  
Nasal  
See note for programs 47-49  
See note for programs 47-49  
See note for programs 47-49  
This response boosts the frequencies that most mix or live sound  
engineers cut because these are the frequencies that are hollow  
and honking.  
 
66  
Program Charts 5  
51  
Proximity Effect  
This curve is meant to mimic the physics phenomenon that the  
closer your ear (or a microphone) gets to a sound source, the  
more the bass is emphasized.  
52  
53  
54  
Presence  
Distance  
This curve gives the signal a little more life when you want to get  
the listener's attention.  
Sometimes you want the signal to not be so much of an attention  
grabber.  
Combfilter Combo  
This is just whacky. This is what happens when you send a stereo  
signal through two different comb filter curves--Channel A using  
a resonant base of 125Hz while Channel B uses a resonant base  
of 50Hz.  
55  
56  
Blank  
Blank  
Store one of your programs here.  
Store one of your programs here.  
 
67  
5 Program Charts  
57  
58  
59  
Blank  
Blank  
Blank  
Store one of your programs here.  
Store one of your programs here.  
Store one of your programs here.  
Notes regarding the Settings Chart on the next page  
Let’s face it; 30 User Memory locations is a lot (not so very long ago, that was unheard of  
for a graphic EQ!), but it’s entirely possible you’ll fill those up someday. So when you get to  
that point, use a copy of the chart on the next page to write down the settings of one of the  
programs you don’t need at the moment. Thanks to the digital heart of the DEQ230, you  
can always get the program back exactly as it was.  
A few notes about filling out the chart:  
1. When a value is exact, like +8 or –4, place a dot in the  
appropriate square above the band.  
2. When the band’s value is zero, or flat, draw a dash through  
that square instead of a dot. This will help you keep track of  
numbers above and below zero by giving you a visual  
reference point (just as the green LED does on the front  
panel). You’ll naturally begin to draw an extended line  
through consecutive bands when they’re all set to zero.  
3. For intermediate values like +3.5, we suggest writing that  
number in the square above that band which most closely  
approximates the actual value.  
4. Don’t forget to record the Channel Level settings and the  
Link status!  
5. Aren’t we thoughtful to have included this chart? We’re sure  
you’ll want to convey your gratitude by buying another Alesis  
product soon. And we’ll convey our gratitude back to you by  
making something really cool that you would’ve wanted to  
buy, anyway!  
 
68  
Program Charts 5  
DEQ230 Settings Chart  
 
69  
5 Program Charts  
This page intentionally left blank  
 
70  
6 Troubleshooting  
WARNING! Following the  
procedures in this section  
will ERASE ALL OF  
Restoring the Factory Programs & Defaults  
YOUR USER PROGRAMS  
and replace them with the  
User programs that shipped  
with the DEQ230. Please be  
certain this is what you want  
to do before going through  
these steps.  
There is a power-up button combination that will restore the  
DEQ230's User programs to the factory default programs. This  
same combination of buttons will reset all of the Setup  
functions to their default values. This procedure is called  
"reinitializing."  
To reinitialize the DEQ230, follow these steps:  
1. Make sure you really want to erase every program you have  
stored. That is what reinitializing the unit does.  
2. If you haven't already done so, turn off the DEQ230.  
3. Turn the unit on while pressing the [DOWN/UP] buttons.  
4. When you see the word "RESET" in large letters over the  
[BAND SELECT] buttons, you may let go of the  
[DOWN/UP] buttons. After a couple of seconds, the DEQ230  
will return to Program mode.  
Line Conditioners and Protectors  
Although the DEQ230 is designed to tolerate typical voltage  
variations, in today’s world the voltage coming from the AC line  
may contain spikes or transients. These can cause audible noises,  
and they can stress your gear and, over time, possibly cause a  
failure. There are three main ways to protect against this, listed in  
ascending order of cost and complexity:  
Line spike/surge protectors. Relatively inexpensive, these are  
designed to protect against strong surges and spikes, acting  
somewhat like fuses in that they need to be replaced if they’ve  
been hit by an extremely strong spike.  
Line filters. These generally combine spike/surge protection  
with filters that remove some line noise (dimmer hash,  
transients from other appliances, etc.). A good example is the  
Isobar™ series from Tripp Lite.  
Care and Maintenance  
Do not spray cleaning  
solution of any sort onto the  
front panel of the DEQ230.  
If a cleaning becomes  
necessary, spray a  
recommended cleaning  
solution onto a cloth first,  
and use the cloth to clean  
the front panel.  
Cleaning  
Disconnect the AC power supply, then use a damp cloth to clean  
the DEQ230’s metal and plastic surfaces. For heavy dirt, use a  
non-abrasive household cleaner such as Formula 409™ or  
Fantastik™. DO NOT SPRAY THE CLEANER DIRECTLY  
ONTO THE FRONT OF THE UNIT AS IT MAY DESTROY  
THE LUBRICANTS USED IN THE SWITCHES AND  
CONTROLS! Spray onto a cloth, and then use the cloth to clean  
the unit.  
 
71  
6 Troubleshooting  
Troubleshooting Index  
Symptoms  
Cause  
Solution  
Test with a known good  
input.  
No audio at outputs.  
Weak output signal.  
Clip LED lights often.  
No input audio.  
Bad cables.  
Destination is turned  
down.  
Replace the cables.  
Check the connections  
and the level of the mixer  
or amp to which the  
DEQ230 is connected.  
Increase level from source  
into DEQ230.  
Boost channel levels of  
quiet program.  
Boost Master Level in  
Setup mode.  
Input level weak.  
Output level weak.  
(Decide which is the case  
by pressing the Bypass  
button.)  
Input level too high.  
Reduce input level at  
source.  
Output level too high.  
Reduce gain of problem  
bands within program.  
(Decide which is the case  
by pressing the Bypass  
button.)  
Reduce channel levels of  
that program.  
Reduce Master Level in  
Setup mode.  
Can’t edit program, can’t  
select new program.  
DEQ230 is locked.  
Unlock DEQ230 in Setup  
mode. Refer to page 46.  
Numeric LED Display  
keeps flashing “Li.”  
Channel B is linked to  
Channel A.  
Edit Channel A  
Unlink the Channels to  
allow independent edits to  
Channel B.  
Numeric LED Display  
keeps flashing “Lo.”  
DEQ230 is locked.  
Unlock DEQ230 in Setup  
mode. Refer to page 46.  
Must de-select all bands in  
order to edit a single band.  
Release Edit Group  
function set to Off.  
Set Release Edit Group  
function to On in Setup  
mode.  
DEQ230 won’t turn  
on/won’t go into Setup  
mode  
Holding down buttons  
when turning on power  
Turn on power first, then  
hold down [STORE]  
button to enter Setup  
mode.  
DEQ230 won’t turn  
on/won’t re-initialize  
Holding down buttons  
when turning on power  
Turn on power first, then  
press [DOWN/UP]  
buttons to re-initialize.  
Analog input is ignored  
Digital input is ignored  
Digital signal present at  
S/PDIF Input  
Change Force Analog  
Input setting in Setup  
mode.  
Force Analog Input is set  
to Analog in Setup mode.  
Ditto.  
 
72  
Troubleshooting 6  
Refer All Servicing to Alesis  
We believe that the DEQ230 is one of the best signal processors  
that can be made using current technology, and should provide  
years of trouble-free use. However, should problems occur, DO  
NOT attempt to service the unit yourself unless you have training  
and experience. Service on this product should be performed only  
by qualified technicians. NO USER-SERVICEABLE PARTS  
INSIDE.  
Obtaining Repair Service  
Before contacting Alesis, check over all your connections, and  
make sure you’ve read the manual.  
Customers in the USA and Canada:  
If the problem persists, contact Alesis and request the Technical  
Support department. Make sure you have the unit’s serial number  
with you. Talk the problem over with one of our technicians; if  
necessary, you will be given a return authorization (RA) number  
and instructions on how to return the unit. All units must be  
shipped prepaid and COD shipments will not be accepted.  
For prompt service, indicate the RA number on the shipping label.  
Units without an RA will not be accepted. If you do not have the  
original packing, ship the unit in a sturdy carton, with shock-  
absorbing materials such as Styrofoam pellets (the kind without  
CFCs, please) or "bubble-pack" surrounding the unit. Shipping  
damage caused by inadequate packing is not covered by the Alesis  
warranty.  
Tape a note to the top of the unit describing the problem,  
including your name and a phone number where Alesis can  
contact you if necessary, as well as instructions on where you want  
the product returned. Alesis will pay for standard one-way  
shipping back to you on any repair covered under the terms of this  
warranty. Next day service is available for a surcharge. Field repairs  
are not authorized during the warranty period, and repair attempts  
by unqualified personnel may invalidate the warranty.  
Customers outside the USA and Canada:  
Contact your local Alesis distributor for any warranty assistance.  
The Alesis Limited Warranty applies only to products sold to users  
in the USA and Canada. Customers outside of the USA and  
Canada are not covered by this Limited Warranty and may or may  
not be covered by an independent distributor warranty in the  
country of sale. Do not return products to the factory unless you  
have been given specific instructions to do so.  
Internet Address:  
Important information and advice is available on our web site:  
Email may be addressed to Support@alesis.com.  
 
73  
6 Troubleshooting  
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74  
Specifications  
DEQ230D  
Analog I/O (switchable)  
Input connectors:  
2 balanced 1/4” TRS jacks  
All measurements done over  
a 22 Hz - 22 kHz range with 1  
kHz sine wave at -1dBFS  
input. Impedances are  
Output Connectors:  
2 balanced 1/4” TRS jacks  
Switch set to +4:  
Nominal input level:  
Maximum input level:  
+4dBu (-15dBFS)  
+19dBu (6.9 Vrms)  
measured at 1 kHz.  
Nominal Output Level:  
Maximum Output Level:  
+4dBu (-15dBFS)  
+19dBu (6.9 Vrms)  
Switch set to –10:  
Nominal input level:  
Maximum input level:  
-10dBV (-16dBFS)  
+6dBV (2.0 Vrms)  
Nominal Output Level:  
Maximum Output Level:  
-10dBV (-16dBFS)  
+6dBV (2.0 Vrms)  
Input impedance:  
Output Impedance:  
10k  
220Ω  
DEQ230  
Input connectors:  
Output Connectors:  
2 balanced 1/4” TRS jacks  
2 impedance-balanced  
1/4” TRS jacks  
Nominal input level:  
Maximum input level:  
-10dBV (-18dBFS)  
+8dBV (2.5 Vrms)  
Nominal Output Level:  
Maximum Output Level:  
-10dBV (-18dBFS)  
+8dBV (2.5 Vrms)  
Input impedance:  
Output Impedance:  
10kΩ  
220Ω  
Audio Performance  
Signal To Noise Ratio:  
THD+N:  
>96 dB A-Weighted, Analog In  
to Analog Out  
<0.005%, Analog In to Analog  
Out  
Frequency Response:  
Power Consumption:  
22-22kHz ± 0.50dB, Analog In  
to Analog Out  
15 Watts Max (100-240 VAC /  
50-60 Hz)  
Mechanical  
Size:  
Rack Spaces:  
Weight:  
1.75" H x 19.0" W x 5" D  
1 Space  
3.0 lbs. (1.4 kg)  
 
75  
Specifications  
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76  
Warranty / Contact  
Alesis LimitedWarranty  
ALESIS CORPORATION ("ALESIS") warrants this product to be free of defects  
in material and workmanship for a period of one (1) year for parts and for a period of  
one (1) year for labor from the date of original retail purchase. This warranty is  
enforceable only by the original retail purchaser and cannot be transferred or assigned.  
For the most effective service, the purchaser should register the purchase on the  
During the warranty period ALESIS shall, at its sole and absolute option, either repair  
or replace free of charge any product that proves to be defective on inspection by  
ALESIS or its authorized service representative. In all cases disputes concerning this  
warranty shall be resolved as prescribed by law.  
To obtain warranty service, the purchaser must first call or write ALESIS at the  
address and telephone number available on the Alesis Website to obtain a Return  
Authorization Number and instructions concerning where to return the unit for  
service. All inquiries must be accompanied by a description of the problem. All  
authorized returns must be sent to ALESIS or an authorized ALESIS repair facility  
postage prepaid, insured and properly packaged. Proof of purchase must be  
presented in the form of a bill of sale, canceled check or some other positive proof  
that the product is within the warranty period. ALESIS reserves the right to update  
any unit returned for repair. ALESIS reserves the right to change or improve design  
of the product at any time without prior notice.  
For more effective  
service and product  
update notices, please  
register your DEQ230  
online at:  
support/warranty.htm  
This warranty does not cover claims for damage due to abuse, neglect, alteration or  
attempted repair by unauthorized personnel, and is limited to failures arising during  
normal use that are due to defects in material or workmanship in the product.  
THE ABOVE WARRANTIES ARE IN LIEU OF ANY OTHER  
WARRANTIES OR REPRESENTATIONS WHETHER EXPRESS OR  
IMPLIED OR OTHERWISE, WITH RESPECT TO THE PRODUCT, AND  
SPECIFICALLY EXCLUDE ANY IMPLIED WARRANTIES OF FITNESS  
FOR A PARTICULAR PURPOSE OR MERCHANTABILITY OR OTHER  
IMPLIED WARRANTIES. Some states do not allow limitations on how long an  
implied warranty lasts, so the above limitation may not apply to you.  
IN NO EVENT WILL ALESIS BE LIABLE FOR INCIDENTAL,  
CONSEQUENTIAL, INDIRECT OR OTHER DAMAGES RESULTING  
FROM THE BREACH OF ANY EXPRESS OR IMPLIED WARRANTY,  
INCLUDING, AMONG OTHER THINGS, DAMAGE TO PROPERTY,  
DAMAGE BASED ON INCONVENIENCE OR ON LOSS OF USE OF THE  
PRODUCT, AND, TO THE EXTENT PERMITTED BY LAW, DAMAGES  
FOR PERSONAL INJURY. Some states do not allow the exclusion or limitation of  
incidental or consequential damages, so the above limitation or exclusion may not  
apply to you.  
THIS CONTRACT SHALL BE GOVERNED BY THE INTERNAL LAWS OF  
THE STATE OF CALIFORNIA WITHOUT REFERENCE TO CONFLICTS  
OF LAWS. This warranty gives you specific legal rights, and you may also have other  
rights required by law which vary from state to state.  
This warranty only applies to products sold to purchasers in the United States of  
America or Canada. The terms of this warranty and any obligations of Alesis under  
this warranty shall apply only within the country of sale. Without limiting the  
foregoing, repairs under this warranty shall be made only by a duly authorized Alesis  
service representative in the country of sale. For warranty information in all other  
countries please refer to your local distributor.  
 
77  
Warranty/Contact  
Alesis Contact Information  
Alesis Distribution, LLC  
Los Angeles, CA USA  
E-mail:  
Website:  
Alesis DEQ230/DEQ230D Reference Manual  
Revision A by Randy Lee, with thanks to Mike Murphy  
Revision B by Randy Lee  
Copyright 2003, Alesis Distribution, LLC. All rights reserved  
Reproduction in whole or in part is prohibited. Specifications  
subject to change without notice.  
7-51-0106-B  
01/28/2003  
 
78  

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