Behringer DEQ1024 User Manual

5.17 Mb



User’s Manual

Version 1.0 June 2003




CAUTION: To reduce the risk of electric shock, do not remove the top cover (or the rear section). No user serviceable parts inside; refer servicing to qualified personnel.

WARNING: To reduce the risk of fire or electric shock, do not expose this appliance to rain and moisture.

This symbol, wherever it appears, alerts you to the presence of uninsulated dangerous voltage inside the enclosure—voltagethat may be sufficient to constitute a risk of shock.

This symbol, wherever it appears, alerts you to important operating and maintenance instructions in the accompanying literature. Please read the manual.


1)Read these instructions.

2)Keep these instructions.

3)Heed all warnings.

4)Follow all instructions.

5)Do not use this device near water.

6)Clean only with a dry cloth.

7)Do not block any ventilation openings. 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-typeplug. 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. If 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, extension cords, and the point at which they exit the unit.

11)Only use attachments/accessories specified by the manufacturer.

12)Use only with the cart, stand, tripod, bracket, or table specified by the manufacturer, or sold with the device. When a cart is used, use caution when moving the cart/ device combination to avoid injury from stumbling over it.

13)Unplug this device during lightning storms or when not used for long periods of time.

14)Refer all servicing to qualified service personnel. Servicing is required when the unit has been damaged in any way, such as power supply cord or plug is damaged, liquid has been spilled or objects have fallen into the device, the unit has been exposed to rain or moisture, does not operate normally, or has been dropped.




Digital Stereo 31-Band24-Bit/96kHz Equalizer/Feedback Destroyer/Dynamics Processor

sUltra high-resolutionprocessor for all EQ, RTA and dynamic applications, especially forDEQ1024PA and audiophile mastering

sUnique TRUE CURVE Function—whatyou see on the faders is what you get as frequency response

sRevolutionary FBQ DETECTION system instantly reveals critical frequencies and can also be used as Audio Analyzer

sAutomatic and ultra-fastFeedback Destroyer plus feedback indication via fader LEDs

s“Inaudible” Noise Gate/Peak Limiter function plus amazing Stereo Imager for spatial enhancement

sAdditional sweepable high and low cut filters for removal of unwanted frequencies like floor rumble and highfrequency noise

sIntegrated Pink Noise generator for perfect room and loudspeaker equalization

sDigital AES/EBU and S/PDIF interface and selectable sample rates (44.1, 48, 96 kHz)

sUltra high-resolution24-bit/96kHz A/D- and D/A converters andhigh-performance24/48-bitMOTOROLA® DSP for ultimate sonic resolution

sRelay-controlledhard-bypasswith anauto-bypassfunction during power failure (failsafe relay)

sHighly accurate, 2 x 12-digitLED meters for easy input and output level setting

sUltra high-quality,illuminated45-mmfaders, sealed rotary controls and illuminated switches

sServo-balancedinputs and outputs ongold-platedXLR and ¼" TRS connectors

sInternal switch-modepower supply for maximum flexibility (100 - 240 V~),noise-freeaudio, superior transient response and lowest possible power consumption

sExtremely rugged construction ensures long life even under the most demanding conditions

sDesigned in Germany. Manufactured under ISO9000 certified management system








Dear Customer,



welcome to the team of

1.1 Before you get started


BEHRINGER users, and




thank you very much for


Initial operation


expressing your confi-




dence in

us by pur-

1.2 The user’s manual


chasing the DEQ1024.




Writing this foreword



for you gives me great





because it

2.1 Front panel ......................................................................


represents the culmi-

2.2 Rear panel ......................................................................


nation of many months




of hard work delivered

3. APPLICATIONS ..........................................................


by our engineering team

3.1 Master equalizer in sound reinforcement systems


to achieve a very am-

bitious goal: to present

3.2 Equalizer in the monitor path ........................................


an outstanding piece of

3.2.1 Priming a monitor system ...................................


equipment that can be

3.3 Using the ULTRAGRAPH DIGITAL in the studio ...........


used in both live and

3.4 Special sound effects ..................................................







thanks to its enormous flexibility. The task of designing our new

4. INSTALLATION .........................................................


DEQ1024 certainly meant a great deal of responsibility, which

4.1 Rack mounting


we assumed by focusing on you, the discerning user and

musician. Meeting your expectations also meant a lot of work

4.2 Audio connections .......................................................


and night shifts. But it was fun, too. Developing a product usually

4.3 Digital connections (AES/EBU and S/PDIF) ..................


brings a lot of people together, and what a great feeling it is



when all who participated in such a project can be proud of

what they’ve achieved.





It is our philosophy to share our enjoyment with you, because

6. WARRANTY ..............................................................


you are the most important member of the BEHRINGER team.




With your highly competent suggestions for new products you’ve




made a significant contribution to shaping our company and making




it successful. In return, we guarantee you uncompromising quality




as well as excellent technical and audio properties at an extremely




reasonable price. All of this will enable you to give free rein to




your creativity without being hampered by budget constraints.




We are often asked how we manage to produce such high-




quality devices at such unbelievably low prices. The answer is




quite simple: it’s you, our customers! Many satisfied customers




mean large sales volumes enabling us to get better purchasing




terms for components, etc. Isn’t it only fair to pass this benefit on




to you? Because we know that your success is our success









I would like to thank all of you who have made the DEQ1024




possible. You have all made your own personal contributions,




from the developers to the many other employees at this company,




and to you, the BEHRINGER user.





My friends, it’s been worth the effort!





Thank you very much,





Uli Behringer




Thank you very much for expressing your confidence in BEHRINGER products by purchasing the ULTRAGRAPH DIGITAL DEQ2496, an extremely high-qualitydigital equalizer withbuilt-in24-bit/96kHz A/D and D/A converters, making it an ideal tool for both live and studio applications.

In addition to graphic EQing, the ULTRAGRAPH DIGITAL gives you a wide array of additional functions, such as feedback destroyer, pink noise generator, limiter/noise gate etc., leaving no wishes open. With these and many more features the DEQ1024 is an absolutely all-purposedevice for your recording or mastering studio and will definitely upgrade your equipment.

+The following user’s manual is intended to familiarize you with the unit’s control elements, so that you can master all the functions. After having thoroughly read the user’s manual, store it at a safe place for future reference.

1.1Before you get started

1.1.1 Shipment

The DEQ1024 was carefully packed at the factory to assure secure transport. Should the condition of the cardboard box suggest that damage may have taken place, please inspect the unit immediately and look for physical indications of damage.

+Damaged units should NEVER be sent directly to us. Please inform the dealer from whom you acquired the unit immediately as well as the transportation company from which you took delivery of the unit. Otherwise, all claims for replacement/repair may be rendered invalid.

1.1.2 Initial operation

Please make sure the unit is provided with sufficient ventilation, and never place the ULTRAGRAPH DIGITAL on top of an amplifier or in the vicinity of a heater to avoid the risk of overheating.

+Faulty fuses must be replaced with fuses of appropriate rating without exception! The correct value of the fuses needed can be found in the chapter “SPECIFICATIONS”.

Power is delivered via the cable enclosed with the unit. All requiered safety precautions have been adhered to.

+Please make sure that the unit is grounded at all times. For your own protection, you should never tamper with the grounding of the cable or the unit itself.

1.1.3 Warranty

Please take a few minutes and send us the completely filled out warranty card within 14 days of the date of purchase. You may also register online at The serial number needed for the registration is located at the top of the unit. Failure to register your product may void future warranty claims.

1.2 The user’s manual

The user’s manual is designed to give you both an overview of the control elements, as well as detailed information on how to use them. In order to help you understand the links between the controls, we have arranged them in groups according to their function. If you need to know more about specific issues, please visit our website at, where you’ll find additional information on mixing consoles, effects units and dynamic processors.





2.1Front panel

Fig. 2.1: Front panel control elements

Use the 45-mmEQ faders to increase or decrease any one of the 31 frequency bands. Each fader has its own red LED.

Use the FADER RANGE switches to regulate increasing/ decreasing in three different levels:+12/-12dB (green LED),+6/-6dB (green LED) and0/-24dB (yellow LED). The last option is well suited for eliminating feedback frequencies, since you can select a very pronounced lowering of a specific frequency range(-24dB).

+Each switch on your DEQ1024 (with the exception of CONFIG and CLOCK) has its own LED that lights up when the respective function is activated.

+All settings you implement always affect both channels of your DEQ1024.

The DEQ1024 features an automatic FEEDBACK DESTROYER.


When you press the ON/OFF switch (yellow LED lights up), the feedback destroyer scans the audio signal for feedback frequencies. As soon as one or more frequencies show feedback, the red LED of theRESET (HOLD) switch lights up. The affected frequencies are then automatically lowered. In addition, your audio program is constantly scanned for new feedback frequencies, and feedback is destroyed as it comes up. This makes sense for microphones that are in constant motion during a stage performance (e. g. vocal microphones), where feedback may arrise constantly.

Deactivating the search function (feedback suppression remains active):

If you now press the ON/OFF switch for a second time, the feedback analysis stops. Those frequencies emitting feedback will continue being lowered (RESET (HOLD) LED is still on). This procedure is well suited for stationary microphones, such as drum microphones. To start the “hunt” for feedback again, hit the ON/OFF switch once again.

Displaying the feedback frequencies:

If you briefly (for approx. 2 seconds) depress the RESET (HOLD) switch, the feedback frequencies that the DEQ1024 was able to find will be indicated on the respective fader LEDs. If no feedback occurs, the LEDs will stop being lit up for roughly 2 seconds.

Deactivating the FEEDBACK DESTROYER:

If you hold the RESET (HOLD) switch depressed for a few seconds, the filter settings are reset (RESET (HOLD) LED dies out) and the FEEDBACK DESTROYER is deactivated.

If you press the FB INDICATOR switch (green switch LED lights up), the FBQ feedback detection system is activated. The frequency (or the frequencies) that cause feedback are now shown in the form of a brightly shining fader LED. All other LEDs are dimmed. Simply lower somewhat the pertinent frequency range until feedback is no longer present and the LED dies out.

By displaying the intensity of individual frequency ranges, the feedback recognition system also functions as an audio analyzer.

+Please keep in mind that the FB INDICATOR only shows the intensity of the individual frequency bands. Not every frequency that is present automatically causes feedback.

+FEEDBACK DESTROYER and FB INDICATOR function independently from one another and can be activated simultaneously. Please bear in mind: when in 96-kHzmode, FEEDBACK DESTROYER and FB INDICATOR arenot available!

When you keep the PINK NOISE switch depressed for a few seconds, the internal pink noise generator of your DEQ1024 is activated (red switch LED lights up) and the volume level of the test signal is gradually increased as long as the switch remains depressed (the level is shown on LEVEL METER). Briefly pressing the PINK NOISE switch once again deactivates the function.


Room resonance and the transmission characteristics of your P.A. system naturally lift certain frequencies while lowering others. Pink noise is a neutral signal that can be played back over the P.A. system in order to measure these room characteristics. One such measurement of the frequency response with a special measurement microphone (e. g. BEHRINGER ECM8000) coupled to a realtime analyzer (integrated in the BEHRINGER ULTRACURVE PRO DEQ2496) delivers the foundation for setting up the equalizer. Boosted frequencies can be lowered by means of your equalizer, while frequencies that are too weak can be boosted, and a nearly linear playback is achieved.




+Try to orient yourself on a frequency whose signal level lies in the 0 dB to -3dB range in order to avoid overdriving the equipment connected (e. g. amp, crossover).

In the world of ordinary graphic equalizers, there is always a difference between the adjusted curve and the resulting frequency response. This phenomenon is simply caused by the construction of such equalizers. This difference depends on the frequency and its cut/boost. Near-byfrequency bands influence one another, whereby individual instances of cut or boost can also be added up to one another.

Fig. 2.2: Graphic equalizer without frequency response correction

This occurrence can be corrected by means of a specially developed algorithm utilized in the ULTRAGRAPH DIGITAL DEQ1024. Simply press the TRUE CURVE switch (green switch LED lights up).

Fig. 2.3: Graphic equalizer with frequency response correction (TRUE CURVE)

The resulting frequency response now corresponds exactly to the settings that you adjusted with the graphic equalizer.

The BYPASS switch lets you directly compare the processed and unprocessed audio program. When the BYPASS function is activated (red switch LED lights up), the input of the unit is directly forwarded to the output so you can monitor the unprocessed signal.

The DYNAMICS section of the DEQ1024 consists of a GATE and a LIMITER. Use theGATE andLIMITER controls to determine the threshold. When the threshold is exceeded (LIMITER) or when the signal falls below the threshold (GATE), the dynamic processors starts affecting the signal.


When the input signal falls below the threshold value, the signal is completely faded out. Tape hiss, crosstalk or disturbing noise can thus be effectively removed from the signal. The yellow GATE LED in the METER section (see) lights up as soon as the GATE closes. The range of the threshold lies between-60and-10dB. When turned all the way to the left, the GATE is deactivated (OFF).


The LIMITER protects your equipment from signal peaks that could for example damage your speakers. Output signal levels that exceed the selected threshold value are limited, and the red LIMITER LED in the METER section (see) lights up. By reducing signal dynamics, a more expressive sound is achieved. The threshold range lies between-6and +9 dB. When turned all the way to the right, the LIMITER is deactivated (OFF).

+Please keep in mind that boosting many frequency bands also increases the output signal level. In this case, the limiter is activated sooner. You can avoid this by achieving signal correction not only by boosting frequency bands but by also lowering signal levels. To achieve creative sound effects, the peak limiter can deliberately be driven to its limits.

The DEQ1024 features a LOW CUT and HIGH CUT filter in its FILTER section, allowing you to limit the entire frequency spectrum upward or downward. The HIGH CUT control is used to determine thecut-offfrequency above which the high frequency range is lowered (2.5 - 16 kHz). When turned all the way to the right, the filter is deactivated (OFF). The LOW CUT control is used to determine thecut-offfrequency above which the low frequency range is lowered (20 - 160 Hz). When turned all the way to the left, the filter is deactivated (OFF).

Use the GAIN control in theMASTER section to determine the output volume of the ULTRAGRAPH DIGITAL in the range between-9to +9 dB. In addition, there is also a stereo imager function that lets you adjust the stereo width and therefore the separation between the left and the right stereo side. When theSTEREO IMAGE control is turned all the way to the right, you achieve the maximum widening of the stereo signal (WIDE); when the control is turned all the way to the left, the stereo signal is transformed into a mono signal (MONO). When the STEREO IMAGE control is in its middle position, your signal is not processed (STEREO).

When you keep the CONFIG switch depressed for a few seconds, you can select the operating mode of your DEQ1024:ANALOG (green LED),DIGITAL (yellow LED), PRE EQ (yellow LED) orPOST EQ (yellow LED). When in the PRE EQ or POST EQ mode, you can use the rear panel digital connectors as inserts, for example for an additional dynamics processor. When the unit is in PRE EQ mode, the insert point is locatedpre EQ; when the unit is in POST EQ mode, the insert point is locatedpost EQ (see fig. 2.5 and 2.6).




Fig. 2.4: Input/output wiring depending on operating mode






































































Tab. 2.1: Input/output wiring depending on operating mode

Fig. 2.5: Signal flow in PRE EQ mode

Fig. 2.6: Signal flow in POST EQ mode

When you keep the CLOCK switch depressed for a few seconds, you can select the desired sample rate with which your DEQ1024 is working:44.1 kHz,48 kHz or96 kHz (green LEDs). To synchronise your DEQ1024 with the sample rate of an external unit (e. g. through a digital mixing console), you have to select theDIG IN setting (yellow LED lights up).

+If you select the DIG IN setting, although no signal is connected to the digital input, the DEQ1024 is not able to synchronise with any sample frequency (yellow DIG IN LED is blinking). In this case the ULTRAGRAPH DIGITAL switches to the sample frequency last connected to the digital input. If you connect a signal to the digital input while operating in the unsynchronised mode, your DEQ1024 switches back to normal mode and synchronises with the connected sample frequency (yellow LED lights up).

To select the word length of the digital output signal (16 bit or 24 bit), keep the CONFIG and CLOCK switches simultaneously pressed. The 24-bitsetting is shown by means of the-24dB LEDs in the METER display (see). When the16-bitsetting is selected, no METER LED lights up. This way, the DEQ1024 can be adjusted to the16-bitinputs of DAT and CD recorders or sound cards. The analog output signal is always converted with 24 bit, independent of the above setting.

The 12-digitLEVEL METER shows the signal level of the input and output signals. Use the METER switch located below it to select the respective signal, whereby the output signal is indicated when the switch LED lights up (green), and the input signal is indicated when the switch LED is not lit. The redCLIP LED lights up as soon as the indicated signal is overdriven. TheGATE and theLIMITER LED shows that the threshold of the respective dynamics processors is either exceeded or is below the selected value; the LED also indicates that the dynamics processor is active at this time (see). Additionally, the volume of the pink noise generator and the24-bitword length setting (see) is shown on the LED METER.

Keeping the STANDBY switch depressed for a few seconds puts the DEQ1024 into standby mode (red switch LED lights up). In this case, the signal connected to the DEQ1024 is looped through without being processed.

+All new settings are saved after approx. 2 seconds, so that powering the DEQ1024 off and then on again

(by using the STANDBY or the POWER switch on the rear panel) recalls the current settings.




2.2 Rear panel

Fig. 2.7: Rear panel control elements and connectors

The balanced XLR and 1/4" TRS inputs are used for connecting an analog input signal.

The analog output signal of the DEQ1024 can be taken by using these balanced XLR and 1/4" TRS connectors.

The MAX. LEVEL switches increase the maximum signal level on the analog inputs and outputs from +12 dBu to +22 dBu.

You can selectively connect an input signal in the AES/ EBU format (via the XLR connector) or in the S/PDIF format (via the RCA connector) to the digital inputs. In PRE EQ and POST EQ modes, these connectors can also be used as insert returns (see ). Here, you can connect the output of your dynamics processor or similar equipment.

+Never connect a signal simultaneously to the AES/EBU and to the S/PDIF input.

The output signal is available on the digital output in the AES/EBU format (XLR connector) and in the S/PDIF format (RCA connector). In PRE EQ or POST EQ mode you can use these connectors as insert sends (see ). Connect the input of your external dynamics processor or similar equipment here. Unlike with the digital inputs, both digital outputs can be used simultaneously.

The POWER switch powers up your ULTRAGRAPH DIGITAL. The POWER switch should always be in its “Off” position when you are about to connect the DEQ1024 to the mains.

+Attention: The POWER switch does not fully disconnect the unit from the mains. Unplug the power cord completely when the unit is not used for prolonged periods of time.

The mains connection is achieved via the standard IEC connector. A matching power cord is included.

You can exchange blown fuses that are located in the FUSES COMPARTMENT of your DEQ1024. Blown fuses must be replaced by fuses of the same type and rating. Please refer to chapter 5 “SPECIFICATIONS” for further details.

SERIAL NUMBER of the ULTRAGRAPH DIGITAL. Please take the time to fill in and return the warranty card within 14 days after the date of purchase. Or register online at


The flexible concept of the ULTRAGRAPH DIGITAL, with its wide-rangingpossibilities for audio processing, opens up many application options. We will now present to you some of those possibilities with their typical settings.

Fig. 3.1: The ULTRAGRAPH DIGITAL DEQ1024 as master equalizer




3.1Master equalizer in sound reinforcement systems

This is surely the most common DEQ1024 application.

To achieve optimal results, you should keep in mind the following:

Before you begin correcting the frequency response, running your audio program “unprocessed” first has proved itself useful. If distortion occurs, it should first be confronted within the P.A. system. The physical location of your loudspeakers also plays a huge role. No equalizer in the world can majorly improve the sound that was thoroughly wattered down by being bounced off the walls and ceilings. Modifying speaker positioning alone can create major improvements in the quality of your sound.

When using multi-wayactive speakers, you should also first correct therun-timeand phase settings (the ULTRADRIVE PRO DCX2496 digital crossover from BEHRINGER gives you all the tools needed for this). Only then does the ULTRAGRAPH DIGITAL come into play. Background noise such as mains hum as well as extremelynarrow-bandresonance should first be eliminated by using the DEQ1024 (also see ch. 3.2.1). This should definitely be done before setting up the sound.

After this editing, you have a basic setup; now, you can do some manual fine-tuning,if necessary.

The following is true:

A linear response curve is not ideal for every application. For example, when dealing with voice transmission, being able to understand the speaker is the most important factor. Therefore, the response curve should drop away in the bass range, since the voice can carry subsonic noise and floor rumble.

As a rule, extremely low and extremely high frequencies are transmitted much weaker. It makes no sense to burden a small P.A. system with frequencies below 50 Hz; the only result in addition to the higher power consumption would most likely be expensive repair costs.

+Always keep in mind where the physical limitations of your system are.

Upon setting up your system as accurately as possible to the desired response curve, walk around the listening area so you can get an idea what your system sounds like from various positions. Don’t forget to implement frequent pauses and a various music selection into your program. You will get a better feeling for the transmission characteristic of your system as well as of the room/auditorium itself.

+Achieving good EQ settings requires a lot of time and patience! If extreme settings of your EQ are required in order to produce a useful frequency response, this should be seen as an alarm sign that a serious error or defect is present somewhere in your sound system, be it in room acoustics or in your equipment.

An equalizer is no solution that can make up for a poor P.A. system, but it is an extremely useful and effective sound tool for musical fine tuning. Fine tuning often lets you create amazing results and improvements in acoustic penetration and in the overall quality of your sound.

3.2 Equalizer in the monitor path

Basically, the on-stagevolume level should be kept as low as possible, because: will be easier on your hearing,

2.there are less feedback problems, and’s easier to achieve a good front-of-housesound.

Often, the volume of the monitor speakers is raised as a concert goes on. Use breaks and pauses to reduce all monitor paths by about 3 dB. The musicians will not or hardly hear that the volume has been reduced, because during a break their hearing can relax a bit. This gives you valuable headroom in your system.

Extremely low frequencies are usually faded out completely to avoid a “muddy” sound on stage caused by low-frequencyfeedback. Use thelow-cutfilter for this purpose and set it up in such a way so that extremely deep feedback disappears, creating atransparent-soundingmonitor sound.


in a monitor system