dbx dbx GoRack dbx gorack

PERFORMANCE PROCESSOR

Owner’s Manual

Warranty

1. Please register your product online at dbxpro.com. Proof-of-purchase is considered to be the responsibility of the consumer. A copy of the original purchase receipt must be provided for any warranty service.

2. dbx warrants this product, when purchased new from an authorized U.S. dbx dealer and used solely within the U.S., to be free from defects in materials and workmanship under normal use and service. This warranty is valid to the original purchaser only and is non-transferable.

3. dbx liability under this warranty is limited to repairing or, at our discretion, replacing defective materials that show evidence of defect, provided the product is returned to dbx WITH RETURN AUTHORIZATION from the factory, where all parts and labor will be covered up to a period of two years. A Return Authorization Number must first be obtained from dbx. The company shall not be liable for any consequential damage as a result of the product’s use in any circuit or assembly.

4. dbx reserves the right to make changes in design or make additions to or improvements upon this product without incurring any obligation to install the same additions or improvements on products previously manufactured.

5. The foregoing is in lieu of all other warranties, expressed or implied, and dbx neither assumes nor authorizes any person to assume on its behalf any obligation or liability in connection with the sale of this product. In no event shall dbx or its dealers be liable for special or consequential damages or from any delay in the performance of this warranty due to causes beyond their control.

Technical Support & Service

If you require technical support, contact dbx Technical Support. Be prepared to accurately describe the problem. Know the serial number of your device – this is printed on a sticker attached to the chassis.

Before you return a product to the factory for service, we recommend you refer to this manual. Make sure you have correctly followed installation steps and operating procedures. For further technical assistance or service, please contact our Technical Support Department at (801) 566-8800 or visit dbxpro.com. If you need to return a product to the factory for service, you MUST first contact our Technical Support Department to obtain a Return Authorization Number.

NO RETURNED PRODUCTS WILL BE ACCEPTED AT THE FACTORY WITHOUT A RETURN AUTHORIZATION NUMBER.

Please refer to the Warranty information, which extends to the first end-user. After expiration of the warranty, a reasonable charge will be made for parts, labor, and packing if you choose to use the factory service facility. In all cases, you are responsible for transportation charges to the factory. If the product is still under warranty, dbx will pay the return shipping.

Use the original packing material if it is available. Mark the package with the name of the shipper and with these words in red: DELICATE INSTRUMENT, FRAGILE! Insure the package properly. Ship prepaid, not collect. Do not ship parcel post.

02

Table of Contents

Overview �� 2

Introduction ��2 Features ��2

User Interface & Connectors �� 3

Top Panel ��3 Rear Panel ��4

Setup �� 5

Making Connections ��5 Configuring The goRack’s Routing ��6 Setting Initial System Levels ��8

Operating The goRack ��10

Master Volume ��10 Output Limiter & Clipping �� 10 Anti-Feedback ��11 Compressor �� 14 Subharmonic Synthesizer ��16 EQ ��18

Application Diagrams �� 22

Application 1: Speech/Presentation �� 22 Application 2: Solo Artist/Duo Performance �� 23 Application 3: Band Performance/DJ �� 24 Application 4: Using Powered Subwoofers ��25

Technical Information �� 26

Audio Cable Diagrams��26 Specifications ��27

Additional Resources �� 28

1

Overview

Introduction

The dbx® goRack™ is an easy-to-operate portable loudspeaker processor. Based on our industry-leading DriveRack® Series processors, the goRack sits next to a set of powered speakers and provides powerful signal processing, including Anti-Feedback, Compression, Subharmonic Synthesis, and EQ. Each processing function can easily be enabled or disabled via the top-panel buttons, and settings can be adjusted via the goRack’s large rotary encoder.

The goRack can be used to provide loudspeaker processing in a conventional sound system by placing it between the mixer and powered speakers/amplifiers or as a stand-alone 2-channel mixer/loudspeaker processor, making it ideal for band rehearsal spaces, live performance of solo artists or duos, weddings, or speech/presentation applications.

The goRack’s rear panel houses combination 1/4” / XLR inputs that can be connected to either mixer outputs, or straight to instrument or microphone outputs. The Mic/Line switch on each input selects the proper input sensitivity while dual gain controls on the top panel provide independent level adjustment. The goRack’s stereo 1/8” Mini Aux Input allows for direct connection of a mobile device or portable music player. The XLR outputs allow for interfacing with powered speakers or stand-alone amplifiers.

The goRack represents the best of dbx’s DriveRack processing in its purest, most simplified form, all housed in a sleek, compact form factor that fits in your hand, or back pocket.

Thanks for choosing dbx.

Features

• 48 kHz / 24-Bit Processing

• 3 Routing Options (Dual Mono Sum, Stereo, & Advanced)

• Anti-Feedback Using dbx’s Proprietary Advanced Feedback Suppression Algorithm

• dbx Compression

• dbx Subharmonic Synthesis For Deep, Punchy Bass

• 16 Selectable EQ Curve Presets

• 2 Combination XLR / TRS Inputs (Selectable Between Mic or Line Level)

• Stereo 1/8” Aux Mini Input

• 2 XLR Outputs

• Output Mute Button

• 7-Segment Display

• Independent Mic / Line Input Level Controls

• Included Power Adapter

2

User Interface & Connectors

1 3 42

5 6

Top Panel

1. 7-Segment Display

This display shows selected options and processor settings.

2. VOLUME (EDIT) Encoder

This rotary encoder is used for adjusting the goRack’s output volume or for editing settings after pressing and holding any of the processor buttons.

VOLUME

(EDIT)

INPUT

SIGNAL

LEFT RIGHT

3. LEFT / RIGHT Input Gain Knobs

Adjust these gains to optimize the signal levels for the main LEFT/RIGHT inputs. The MIC/ LINE switches on the rear panel should be set to the correct position for the application before adjusting these knobs.

NOTE: AUX INPUT signals are not affected by

the Input Gain knobs.

4. INPUT SIGNAL LEDs

These multi-colored LEDs display the input signal level strength and available headroom.

•

Green

Indicates signal is present.

Orange

• Indicates the signal level is approaching the headroom limit.

• Red Indicates the input signal is clipping and the input gain should be reduced.

5. MUTE (MODE) Button

Pressing this button will mute/unmute the goRack’s outputs. Pressing and holding this button for 2 seconds enters Routing mode (indicated by a flashing LED), where you can select a routing option. See ‘Configuring The goRack’s Routing’ on page 6 for more information on the routing options available in the goRack.

9 9

MODE

ANTI-FEEDBACKMUTE

(HOLD) EDIT

SUB SYNTH

EQCOMPRESSOR

6. Processor Buttons

Pressing each of these buttons will enable/disable the corresponding processor type (LED off = processor disabled, LED on = processor enabled). Pressing and holding each button for 2 seconds will enter Edit mode (indicated by a flashing LED), where the selected processor can be edited using the VOLUME (EDIT) encoder.

3

Rear Panel

2

1 4 6

3 5

1. LEFT / RIGHT Combination Input Jacks

Connect your mixer, microphone, or instrument outputs to these combination 1/4” / XLR input jacks. The input sensitivity of these jacks are set using the MIC/LINE switches next to each jack and the input gain can be adjusted using to the top-panel LEFT/RIGHT input gain knobs.

The input signals can be routed in stereo or mono summed to the output jacks. See ‘Configuring

The goRack’s Routing’ on page 6 for

more information on the Routing modes available in the goRack.

2. MIC / LINE Switches

Match these swtches to the type of connections being made to the input jacks. Select the LINE option when connecting the outputs of a line-level device, such as a mixer or the output of an instrument with a built-in pickup. Select the MIC option when connecting a microphone.

3. AUX INPUT Jack

Connect a mobile device or portable music player to this 1/8” (3.5mm) stereo Mini jack. There are a couple of different processing routing options available for this jack (see ‘Configuring The goRack’s Routing’ on page 6 for more information).

4. XLR Output Jacks

Connect these electronically balanced XLR outputs to the amplifier or powered speaker inputs.

5. DC Power Input Jack

Connect the included Harman power adapter to this power input jack.

6. Power Adapter Cord Retaining Clip

Route the power adapter cord through this retaining clip to prevent accidental removal of the power plug (see ‘Applying Power’ on page 5 for more information).

4

Setup

2”

Making Connections

Audio Connections

1� Ensure the power is turned off on all interconnecting equipment and the goRack before making audio connections.

2� Connect the outputs of the mixing console, microphones, or instruments to the inputs of the goRack and set the goRack’s

MIC/LINE input switches accordingly. Use the highest quality cable available with the shortest possible cable runs.

3� Connect the goRack’s outputs to the amplifier or powered speaker inputs.

TIP: See ‘Application Diagrams’ on page 22 for application notes and system diagrams which can be used for

reference when connecting the goRack to your system. See ‘Audio Cable Diagrams’ on page 26 for information on cable wiring.

Applying Power

1� Ensure your power amplifiers or powered speakers are turned off. 2� As shown in the illustration to the right, pinch the power adapter cord together, leaving

approximately 2 inches of cable before the power plug, then route the cord into the cord retaining clip on the goRack’s rear panel.

3� Connect the power adapter jack to the DC power input.

4� Apply power to the goRack by connecting the other end to an available AC power outlet. Since

the goRack does not have a power switch, an AC power strip or power conditioner can be used for switching power to the goRack on or off.

5� Apply power to your mixer then your power amplifiers or powered speakers.

WARNING! When powering up a fully connected PA system, it is advisable to ALWAYS turn on the goRack (and

mixer if applicable) first then turn on your amplifiers or powered speakers last. It’s also a good idea to ensure the goRack VOLUME or mixer output gains are reduced before applying power to the amplifiers. When powering down the system, you should ALWAYS power down the amplifiers/powered speakers first, wait about 10 seconds to allow them to discharge, then power down the goRack (and mixer if applicable). In short, every time you use your system, the power amps should be the last components turned on and the first components turned off.

5

Conﬁguring The goRack’s Routing

0

OUTPUTS

MIC/LINE

0

OUTPUTS

MIC/LINE

OUTPUTS

L R

AF

COMP

SUB

EQ

MIC/LINE

INPUTS

L

R

AUX

INPUT

L

R

0

OUTPUTS

L R

AF

COMP

SUB

EQ

MIC/LINE

INPUTS

L

R

AUX

INPUT

L

R

OUTPUTS

L R

AF

COMP

SUB

EQ

MIC/LINE

INPUTS

L

R

AUX

INPUT

L

R

OUTPUTS

MIC/LINE

The goRack offers 3 routing options to select from. The following table provides a description of each of these routing options.

Routing Options

Option Type Description Routing Diagram

This is the default setting from the

1

2

Mono

Stereo

factory. This option mono sums all input signals and feeds them to both outputs. This option is ideal for the solo artist or duo. For example, one input could be used for connecting a microphone and the other for an instrument, such as an acoustic guitar with a built-in pickup. This option is also well-suited for speech/presentation applications.

This option maintains stereo imaging through the goRack. Select this option when connecting the goRack between the mixer and powered speakers or amplifier in a conventional, stereo PA system.

NOTE: Since the Subharmonic

Synthesis effect manipulates lower frequencies, it is a mono effect. If absolute stereo separation is required, the Subharmonic Synthesis effect should be turned off.

INPUTS

AUX

INPUT

INPUTS

AUX

INPUT

L R

COMP

AF

SUB

EQ

L R

COMP

SUB

EQ

L R

Advanced

3

This option mono sums the MIC/ LINE inputs just like option 1, but maintains stereo imaging in the AUX INPUT. It also moves the Subharmonic Synthesis processing and adds EQ processing to the AUX INPUT. Use this option when you don’t want signals connected to the MIC/LINE inputs to be processed with Subharmonic Synthesis and want to add equalization to the AUX INPUT signal.

COMP

AF

AUX

L R

EQ

SUB

INPUTS

INPUT

LEGEND AF = Anti-Feedback COMP = Compressor SUB = Subharmonic Synthesiser EQ = Equalizer

L R

6

To select a Routing option:

0

070

VOLUME

INPUT

SIGNAL

(EDIT)

LEFT RIGHT

1. Press and hold the MUTE (MODE) button for 2 seconds (the LED will flash, indicating Route mode is active).

2. Select the desired option by turning the VOLUME (EDIT) encoder.

1

9 9

MODE

2

9 9

MODE

ANTI-FEEDBACKMUTE

VOLUME

(EDIT)

ANTI-FEEDBACKMUTE

VOLUME

(EDIT)

(HOLD) EDIT

SUB SYNTH

EQCOMPRESSOR

INPUT

SIGNAL

LEFT RIGHT

EQCOMPRESSOR

INPUT

SIGNAL

LEFT RIGHT

3. When done, press any button to exit Route mode.

0

9 9

MODE

ANTI-FEEDBACKMUTE

(HOLD) EDIT

SUB SYNTH

EQCOMPRESSOR

7

Setting Initial System Levels

Powered

060

070

Properly setting system levels will help keep distortion and noise levels down, improve anti-feedback operation, and provide ample headroom for clean and safe operation of the sound system.

To set system levels:

1. Turn down your amp or powered speaker levels. If your powered speakers have Mic/Line switches, set them to “Line”.

2. Make sure all processors are turned off.

Amplifier or

VOLUME

(EDIT)

0

9 9

ANTI-FEEDBACKMUTE

MODE

VOLUME

(HOLD) EDIT

(EDIT)

LEFT RIGHT

SUB SYNTH

LEFT RIGHT

Speakers

INPUT

SIGNAL

EQCOMPRESSOR

INPUT

SIGNAL

3. Turn the VOLUME encoder to 70.

8

0

9 9

MODE

ANTI-FEEDBACKMUTE

(HOLD) EDIT

SUB SYNTH

EQCOMPRESSOR

4. With signal present on the LEFT/RIGHT inputs, adjust the LEFT and

070

Powered

080

RIGHT input gain knobs until the INPUT SIGNAL LEDs occasionally light orange.

Note that the INPUT SIGNAL LEDS also indicate signal level for the AUX input. However, the LEFT/RIGHT input gains will only adjust level for the LEFT/RIGHT inputs. Levels for the AUX input should be adjusted using the output level control available in the connected device.

0

9 9

MODE

INPUT

VOLUME

(EDIT)

ANTI-FEEDBACKMUTE

(HOLD) EDIT

SUB SYNTH

SIGNAL

LEFT RIGHT

EQCOMPRESSOR

Amplifier or

Speakers

5. Turn up the volume on your amp or powered speakers until the desired level is achieved – do not turn them up so far that the “Clip” or “Limit” LEDs light. If Clip or Limit LEDs light, the volume controls should be lowered until they no longer light.

INPUT

SIGNAL

LEFT RIGHT

EQCOMPRESSOR

6. Further system level adjustments can be made during the performance using the goRack’s VOLUME encoder if required.

0

9 9

MODE

VOLUME

(EDIT)

ANTI-FEEDBACKMUTE

(HOLD) EDIT

SUB SYNTH

TIP: If additional system level is required or the source levels are too dynamic (meaning the source levels vary dramatically

between soft and loud), try enabling and adjusting the compressor. See ‘Compressor’ on page 14 for further information on using the compressor.

9

Operating The goRack

070

0

This section of the manual describes the processing types available and how to operate the goRack.

Master Volume

When the goRack initially boots, the VOLUME encoder will control master output volume. This is the default operating mode. Volume is controlled post-compression and pre-limiting.

To adjust master volume:

INPUT

VOLUME

(EDIT)

SIGNAL

LEFT RIGHT

1. Turn the VOLUME encoder clockwise to raise the output volume or counter-clockwise to lower the volume.

0

9 9

MODE

ANTI-FEEDBACKMUTE

(HOLD) EDIT

SUB SYNTH

EQCOMPRESSOR

Output Limiter & Clipping

A non-editable limiter is in place on the outputs to prevent harsh digital clipping. You may hear the limiter affecting the signal if your output levels get too close to clipping.

A small dot in the lower right hand corner of the display will light if the output channels are driven into clipping. This occurs if you have added too much gain to your signal via the Compressor, Sub Synth, or EQ processing modules. If you see this dot light, your signal is clipping and you need to turn it down. The easiest way to do this is to lower the master volume using the VOLUME encoder. You may also want to adjust your input gains, Compressor amount, Sub Synth amount, or EQ setting to help avoid clipping.

7

0.

10

Anti-Feedback

Feedback is caused when an in-phase audio loop is created between an input transducer (such as a guitar pickup or microphone) and an output transducer (a loudspeaker). The goRack includes the exclusive AFS™ (Advanced Feedback Suppression) algorithm to help combat this dreadful phenomenon. The 10 Live AFS filters will automatically detect and suppress feedback. Just press the ANTI-FEEDBACK button and the goRack will do the rest.

AFS uses precision frequency detection and state-of-the-art processing to determine the exact range of feedback frequencies to remove (instead of indiscriminately removing large sections of audio). In the past, graphic equalizers were used to eliminate feedback from a system. This was an acceptable method for eliminating feedback, but when this method is put up against precision notch filters, such as those found in AFS, it becomes very evident that using graphic equalizers for this task severely affects the tone of the system. With AFS, the precision filters remove only a fraction of the frequency spectrum, eliminating the feedback with far less audible artifacts. The below diagram shows a comparison of filter widths between the AFS filters and conventional 1/3 octave graphic EQ filters.

Filter Precision Comparison Chart

TIP: AFS works best when the signal entering the goRack’s inputs is sufficient. If the signal level is too low, AFS may be

slow to respond to feedback. See ‘Setting Initial System Levels’ on page 8 for further information on setting the goRack’s input gains.

11

Available Anti-Feedback Options

0

The Anti-Feedback options available in the goRack allow you to adjust the width of the notch filters. A description of each of these options is provided in the following table.

Anti-Feedback Width Options

Option Application Type Description

This setting has a constant bandwidth of 8 Hz below 927 Hz and a constant Q of 116 at or above 927 Hz. This option is optimized for live music sound reinforcement and offers the highest level of sonic quality. When this option is selected, the AFS algorithm will zero in on the offending feedback frequency, while leaving the surrounding frequencies unscathed. With this option selected, the AFS filters will take slightly longer to set than when using the MUSIC/SPEECH setting, although the difference in time will be quite negligible.

This setting has a constant bandwidth of 9 Hz below 260 Hz and a constant Q of 29 at or above 260 Hz. This option is optimized for live music or speech sound reinforcement and provides the best all-around protection. It will provide the best combination of fast feedback suppression and precision, using filters slightly narrower and less audible than the SPEECH setting, but slightly faster than the MUSIC setting. If you’re not sure which setting to use or the system is being used for music and speech sound reinforcement, select this option.

1

2

MUSIC

(NARROW)

MUSIC/SPEECH

(MEDIUM)

This setting has a constant bandwidth of 11 Hz below 76 Hz and a

SPEECH

3

WARNING! If AFS is turned on and filters are set (in use), be careful when turning AFS off, as all filters will be

immediately removed from the signal path and sudden feedback could occur. It is recommended that you lower your mixer output volume or the goRack’s output volume before turning AFS off.

NOTE: When all the AFS filters have been set, they will begin to round robin – meaning that if all filters have been set

and new feedback occurs, the first filter set will be released then re-set at the new feedback frequency location.

(WIDE)

constant Q of 7 at or above 76 Hz. This option is optimized for speech sound reinforcement, where wider notch filters are less noticeable. Select this option when using the sound reinforcement system for speech only. With this option selected, notch filters will be wider, but will provide the fastest, most solid protection against feedback.

12

To use Anti-Feedback:

070

0

070

1. Press the ANTI-FEEDBACK button to enable the Anti-Feedback module (the LED will light, indicating the processing module is enabled).

2. To adjust the filter width options, press and hold the ANTI-FEEDBACK button for 2 seconds (the ANTI-FEEDBACK LED will flash, indicating Anti-Feedback Edit mode is active).

0

9 9

MODE

2

9 9

MODE

INPUT

VOLUME

(EDIT)

ANTI-FEEDBACKMUTE

VOLUME

(EDIT)

ANTI-FEEDBACKMUTE

(HOLD) EDIT

SUB SYNTH

SIGNAL

LEFT RIGHT

EQCOMPRESSOR

INPUT

SIGNAL

LEFT RIGHT

EQCOMPRESSOR

3. Turn the VOLUME (EDIT) encoder to select the desired filter width option (see ‘Available Anti-Feedback Options’ on page 12 for option descriptions).

4. When done, press any button to exit Edit mode.

Note that any set AFS filters will be automatically cleared whenever the AFS button is disabled or the goRack is power cycled.

3

9 9

MODE

0

9 9

MODE

INPUT

VOLUME

(EDIT)

ANTI-FEEDBACKMUTE

VOLUME

(EDIT)

ANTI-FEEDBACKMUTE

(HOLD) EDIT

SUB SYNTH

SIGNAL

LEFT RIGHT

EQCOMPRESSOR

INPUT

SIGNAL

LEFT RIGHT

EQCOMPRESSOR

13

Compressor

070

A compressor is used to compress the dynamic range of the audio signal, bringing up the softer portions of the signal and lowering the louder ones. In live sound applications, it is common to compress the audio at different stages in the signal chain. For example, you may apply compression to individual instruments using the mixer’s channel inserts. It is also common practice to apply compression to a group of instruments using the mixer’s bus or group inserts. You can also apply a final stage of compression to the entire mix (commonly referred to as mixbus compression) in order to add some additional “body” and “glue” to the mix.

If connecting microphones or instruments directly to the goRack and using it as a 2-channel mixer, more compression can be used in order to level out the sound sources and provide a more consistent and professional sound on dynamic sources, such as vocals, speech, acoustic guitar, and bass. If using a dedicated mixer along with dedicated compression on individual channels, the compressor in the goRack can be used more judiciously for adding a small dose of additional dynamics control to the entire mix.

Typically, a compressor has two, three, or more parameters to adjust, making them difficult to set for the novice user. The most common parameters on a compressor are the threshold, ratio, and makeup gain. The threshold sets the level at which compression will occur, the ratio sets how much compression will occur once the threshold is exceeded, and the makeup gain raises the output level to compensate for level lost due to compression. Oftentimes, there will also be attack and release controls for adjusting how quickly the compressor will react and release its compression.

Compressors also have a knee, which affects the transition in and out of compression. A compressor’s knee can be hard, soft, or selectable between the two. A hard-knee compressor provides a more aggressively compressed sound, whereas a soft-knee compressor will typically sound more gentle and smooth; OverEasy™ is the term used for dbx soft-knee compressors.

The compressor in the goRack is modeled after the classic dbx 163 analog compressor line. It is a soft-knee (OverEasy) compressor with a fixed ratio of infinity:1, program-dependent auto attack and release times, and one parameter which affects both the threshold and makeup gain under the hood. The soft-knee compression curve helps prevent over-compression due to the high ratio used. The combination of these features make it very easy to obtain professional results with minimal effort when setting the goRack’s compressor.

Available Compressor Parameter

COMPRESSION AMOUNT [1 - 99]

Adjusts the amount of compression applied, with 1 being essentially no compression and 99 being the maximum amount of compression.

To use the Compressor:

INPUT

SIGNAL

LEFT RIGHT

1. Press the COMPRESSOR button to enable the Compressor module

0

9 9

VOLUME

(EDIT)

(the LED will light, indicating the processing module is enabled).

ANTI-FEEDBACKMUTE

MODE

(HOLD) EDIT

SUB SYNTH

EQCOMPRESSOR

14

2. To edit the compressor, press and hold the COMPRESSOR button

040

050

070

for 2 seconds (the COMPRESSOR LED will flash, indicating Compressor Edit mode is active).

5

9 9

MODE

INPUT

VOLUME

(EDIT)

ANTI-FEEDBACKMUTE

VOLUME

(EDIT)

(HOLD) EDIT

SUB SYNTH

SIGNAL

LEFT RIGHT

EQCOMPRESSOR

INPUT SIGNAL

LEFT RIGHT

3. While auditioning the sound source(s), turn the VOLUME (EDIT) encoder until the desired amount of compression is achieved.

4. When done, press any button to exit Edit mode.

0

9 9

MODE

0

9 9

MODE

ANTI-FEEDBACKMUTE

VOLUME

(EDIT)

ANTI-FEEDBACKMUTE

(HOLD) EDIT

SUB SYNTH

EQCOMPRESSOR

INPUT SIGNAL

LEFT RIGHT

EQCOMPRESSOR

NOTE: Applying too much compression can have adverse side effects, such as level “pumping” or potential increased risk

of system feedback. If these conditions occur, it is recommended that the compression amount be reduced.

NOTE: When applying compression, make sure the “Clip” or “Limit” LEDs on your amp or powered speakers do not light.

15

Subharmonic Synthesizer

070

030

dbx subharmonic synthesis (or sub synth) processing has been specifically optimized to enhance the low frequencies in audio material and was designed for use in a variety of professional audio applications, including nightclub and dance DJ mixing, theatre and film sound, sound design, music recording, live music performance, and broadcasting. In certain applications, using traditional EQ to enhance this extremely low frequency region typically does not provide desirable results and can increase noise potential and stage rumble (low-frequency feedback) in live PA systems. Another problem is that the audio source may not have sufficient low end in this region to boost or the mics used to capture the sound may not capture these extremely low frequencies.

Subharmonic synthesis looks at frequencies around 100 Hz in the audio program and creates synthesized frequencies an octave below, providing noise free low-end enhancement that people can really feel! Subharmonic synthesis is best suited for sound systems utilizing subwoofers and in applications where deep low-end response is required.

Available Subharmonic Synth Parameter

SUBHARMONIC SYNTHESIS LEVEL [1 - 99]

Adjusts the amount of subharmonic synthesis effect added to the signal, with 1 being essentially no effect and 99 being the maximum amount of effect.

To use the Subharmonic Synthesizer:

1. Press the SUB SYNTH button to enable the Sub Synth module (the LED will light, indicating the processing module is enabled).

2. To edit the sub synth, press and hold the SUB SYNTH button for 2 seconds (the SUB SYNTH LED will flash, indicating Sub Synth Edit mode is active).

0

9 9

MODE

0

9 9

MODE

INPUT

VOLUME

(EDIT)

ANTI-FEEDBACKMUTE

VOLUME

(EDIT)

ANTI-FEEDBACKMUTE

(HOLD) EDIT

SUB SYNTH

SIGNAL

LEFT RIGHT

EQCOMPRESSOR

INPUT

SIGNAL

LEFT RIGHT

EQCOMPRESSOR

16

VOLUME

040

070

INPUT

SIGNAL

(EDIT)

LEFT RIGHT

3. While auditioning the sound source(s), turn the VOLUME (EDIT) encoder to set the desired amount of sub synth effect.

4. When done, press any button to exit Edit mode.

5

9 9

MODE

0

9 9

MODE

ANTI-FEEDBACKMUTE

VOLUME

(EDIT)

ANTI-FEEDBACKMUTE

(HOLD) EDIT

SUB SYNTH

EQCOMPRESSOR

INPUT

SIGNAL

LEFT RIGHT

EQCOMPRESSOR

IMPORTANT! The subharmonic synthesis process produces low-frequency audio signals that some speakers may

not be designed to reproduce. Attempting to achieve enhanced low end with these systems may not be possible and may result in over-stressing your loudspeakers. If you can’t hear a discernable difference when raising the sub synth effect, it is recommended that you disable the effect. For best results, subwoofers should be used with the sub synth effect.

TIP: If you experience low-frequency artifacts on a voice when using subharmonic synthesis with a dedicated mixer, try

engaging a high pass filter, using EQ, or a combination thereof on the vocal’s mixer channel to reduce the artifacts. If a high pass filter and EQ are not enough, try lowering the amount of subharmoic synthesis applied to the signal.

If you’re using the goRack as a 2-chanel mixer and you wish to use subharmonic synthesis processing on music played through the goRack’s AUX INPUT jack and don’t want vocals or instruments to be treated with the sub synth effect, select the goRack’s routing 3 option. See ‘Configuring The goRack’s Routing’ on page 6 for more information on changing routing options.

17

EQ

0

Various factors will determine how a sound system will sound in a room, such as the frequency response of the speakers, the frequency response of any microphones or instruments used, and the room acoustics to name a few. The goRack has 16 EQ preset curves to select from. These EQ preset curves can be used to quickly tune the frequency response of the sound system to help compensate for some of these limitations and help improve clarity and impact. The EQ can be turned on or off using the EQ button.

Available EQ Presets The following table describes each of the available EQ preset curves.

EQ Presets

Option Name Description EQ Curve

This EQ curve can help when the system sounds

1

Bass

Boost

“thin” and lacks “body” and is similar to raising the LOW tone control on a stereo system.

2

3

4

More

Sub

Venue

EDM/

Pop

Select this curve when the system has body but lacks definition in the bass.

This EQ curve works well when the system is slightly “bright” and the bass frequencies are lacking. Try this curve when the room is a bit reverberant due to brightly reflective surfaces, such as windows.

This curve provides enhanced bass and treble frequencies with a midrange scoop and is well suited for Electronic Dance and Pop Music or DJ use. This is the classic “smiley face” EQ curve.

18

EQ Presets

0

010

Option Name Description EQ Curve

This EQ curve will enhance the bass while simultaneously scooping out some lower-midrange “mud” and slightly reducing the midrange and treble frequencies, providing a deeper, sub-bass sound.

Select this curve to tame treble frequencies when a system sounds overly “bright” and “harsh”. It is similar to lowering the HIGH tone control on a stereo system.

This curve is optimized for live reproduction of an acoustic guitar performance.

5

6

7

Deep

Treble

Cut

Acoustic

8

9

0

Rock

Loudness

Mid

Boost

This curve is well suited for the reproduction of a live rock music performance.

This curve can be used to balance the system’s frequency response when operated at lower system levels. It is optimized to provide a “perceptually flat” response at 80 dB SPL.

This EQ curve can help add midrange definition to a sound system that lacks it.

19

EQ Presets

010

Option Name Description EQ Curve

This EQ curve can reduce

1

2

3

De-Mud

Speech

Mid Cut

“mud” which can build up around the 300 Hz region.

This curve can help reduce low-frequency noise and increase intelligibility in systems reproducing speech only.

This curve can help tame a system that sounds “boxy” or has excessive midrange frequencies and make it sound more musical.

4

5

6

Bass Cut

Jazz

Treble

Boost

Select this curve to tame bass and lower-midrange frequencies when a system sounds “boomy” and “muddy” and is similar to lowering the LOW tone control on a stereo system.

This curve is optimized for the reproduction of a live jazz performance.

This curve can help add top-end “air” and “clarity” to a speaker system that lacks it and is similar to raising the HIGH tone control on a stereo system.

20

To use the EQ:

070

0

070

VOLUME

INPUT

SIGNAL

(EDIT)

LEFT RIGHT

1. Press the EQ button to enable the EQ module (the LED will light, indicating the processing module is enabled).

2. To change the EQ setting, press and hold the EQ button for 2 seconds (the EQ LED will flash, indicating EQ Edit mode is active).

3. While auditioning the sound system, turn the VOLUME (EDIT) encoder and select the EQ curve that sounds best for the application.

0

9 9

MODE

1

9 9

MODE

5

9 9

ANTI-FEEDBACKMUTE

VOLUME

(EDIT)

ANTI-FEEDBACKMUTE

VOLUME

(EDIT)

(HOLD) EDIT

SUB SYNTH

EQCOMPRESSOR

INPUT

SIGNAL

LEFT RIGHT

EQCOMPRESSOR

INPUT

SIGNAL

LEFT RIGHT

4. When done, press any button to exit Edit mode.

MODE

0

9 9

MODE

ANTI-FEEDBACKMUTE

VOLUME

(EDIT)

ANTI-FEEDBACKMUTE

(HOLD) EDIT

SUB SYNTH

EQCOMPRESSOR

INPUT

SIGNAL

LEFT RIGHT

EQCOMPRESSOR

21

Application Diagrams

Speech/Presentation Connections

Use these diagrams and notes for reference when initially connecting and configuring the goRack for your application.

Application 1: Speech/Presentation

This application is suited for speech/presentation applications and provides a 2-channel mixer, aux input, and system processing. The microphone can be connected to the goRack’s MIC/LINE 1 input. If a second microphone is required, the MIC/LINE 2 input can be used. The AUX INPUT can be used for connecting a portable device for audio playback.

Application Notes:

• Make sure your powered speakers (or amplifiers) are turned off before making connections.

• Make connections as described in ‘Making Connections’ on page 5 then apply power to the system according to the instructions described in ‘Applying Power’ on page 5.

• The routing 3 option will work best for this application. See ‘Configuring The goRack’s Routing’ on page 6 for information on goRack routing options.

Set to

MIC

Microphone

Optional

Portable

Device

Stereo Cable

Line Inputs

Powered

Speaker

Included Harman

Power Adapter

Powered

Speaker

NOTE: A stereo (Tip-Ring-Sleeve) Mini cable should be used for the connection between the portable device and AUX

INPUT. See ‘Audio Cable Diagrams’ on page 26 for more information on these cable types.

22

Application 2: Solo Artist/Duo Performance

Microphone/Instrument Connections

This application is suited for solo artist/duo performance applications and provides a 2-channel mixer with system processing. The goRack’s two combination MIC/LINE inputs can be used for connecting microphones or direct instruments. The AUX INPUT can be used for connecting a mobile device or music player for backing tracks or music playback between sets.

Application Notes:

• Make sure your powered speakers (or amplifiers) are turned off before making connections.

• Make connections as described in ‘Making Connections’ on page 5 then apply power to the system according to the instructions described in ‘Applying Power’ on page 5.

• The routing 3 option will work best for this application. See ‘Configuring The goRack’s Routing’ on page 6 for information on goRack routing options.

Set to

MIC

Set to

LINE

Included Harman

Power Adapter

Stereo Cable

Line Inputs

Microphone

Optional

Acoustic Guitar

w/ Pickup

Portable

Music Player

Powered

Speaker

NOTE: A stereo (Tip-Ring-Sleeve) Mini cable should be used for the connection between the portable music player and

AUX INPUT. If connecting instruments to the goRack’s LEFT/RIGHT inputs using 1/4” plugs, unbalanced TS (Tip-Sleeve) instrument cables should be used. See ‘Audio Cable Diagrams’ on page 26 for more information on these cable types.

Powered

Speaker

23

Application 3: Band Performance/DJ

Mixer

Speaker

Mixer Connections

This application is suited for band rehearsal spaces, small venue live performances, or small DJ applications where the sound system already consists of a dedicated mixer and the goRack is used for system processing only. The goRack’s two combination MIC/LINE inputs can be connected to the mixer’s left/right master outputs. Stereo imaging will be maintained through the system when using the LEFT/RIGHT inputs and the pan pots on the mixer can be used to place sound sources in the stereo field if required.

Application Notes:

• Make sure your mixer and powered speakers (or amplifiers) are turned off before making connections.

• Make connections as described in ‘Making Connections’ on page 5 then apply power to the system according to the instructions described in ‘Applying Power’ on page 5.

• The routing 2 option will work best for this application. See ‘Configuring The goRack’s Routing’ on page 6 for information on goRack routing options.

Set to

LINE

Set to

LINE

Right Master Out

Left Master Out

Line Inputs

Powered

Included Harman

Power Adapter

Powered

NOTE: For best noise performance, balanced cables (XLR or 1/4” TRS Phone) should be used between the mixer and

goRack if the mixer’s outputs are balanced. See ‘Audio Cable Diagrams’ on page 26 for more information on these cable types.

24

Application 4: Using Powered Subwoofers

Powered Subwoofer Connections

This application is just like application 3 but with the addition of subwoofers and is better suited for larger DJ or live performance applications. This type of configuration allows the goRack’s sub synth processing to be fully utilized. Powered subwoofers designed for live sound use typically contain a built-in active crossover and additional line-level outputs that can be connected to the main powered speakers, eliminating the need for an external active crossover.

Application Notes:

• Make sure your mixer and powered speakers (or amplifiers) are turned off before making connections.

• Make connections as described in ‘Making Connections’ on page 5 then apply power to the system according to the instructions described in ‘Applying Power’ on page 5.

• The routing 2 option will work best for this application. See ‘Configuring The goRack’s Routing’ on page 6 for information on goRack routing options.

Set to

LINE

Set to

LINE

Right Master Out

Left Master Out

Mixer

Powered Main

Speaker

Powered

Subwoofer

Included Harman

Power Adapter

Powered Main

Speaker

Powered

Subwoofer

NOTE: For best noise performance, balanced cables (XLR or 1/4” TRS Phone) should be used between the mixer and

goRack if the mixer’s outputs are balanced. See ‘Audio Cable Diagrams’ on page 26 for more information on these cable types.

25

1/4” TS PHONE TO TRS PHONE

FROM SOURCE DEVICE (OUTPUT)

TO NEXT DEVICE (INPUT)

TIP

(HOT +)

RING

(COLD –)

SLEEVE

(GROUND)

TIP

(HOT +)

SLEEVE

(GROUND)

HOT +

COLD –

SLEEVE

RCA PHONO TO 1/4” TRS PHONE

FROM SOURCE DEVICE (OUTPUT)

TO NEXT DEVICE (INPUT)

TIP

(HOT +)

RING

(COLD –)

SLEEVE

(GROUND)

HOT +

COLD –

SLEEVE

TIP

(HOT +)

SLEEVE

(GROUND)

RCA PHONO TO 1/4” TS PHONE

FROM SOURCE DEVICE (OUTPUT)

TO NEXT DEVICE (INPUT)

TIP

(HOT +)

SLEEVE

(GROUND)

HOT +

SLEEVE

TIP

(HOT +)

SLEEVE

(GROUND)

1/4” TS PHONE TO RCA PHONO

FROM SOURCE DEVICE (OUTPUT)

TO NEXT DEVICE (INPUT)

TIP

(HOT +)

SLEEVE

(GROUND)

HOT +

SLEEVE

TIP

(HOT +)

SLEEVE

(GROUND)

1/4” INSERT CABLE

GROUND TIP +

TIP + (SEND)

RING + (RETURN)

GROUND

GROUND –

TIP +

RING +

To Input of Device

To Insert

Tip / Send

Ring / Return

To Output of Device

RING +GROUND

1/4” TS PHONE TO TRS PHONE

FROM SOURCE DEVICE (OUTPUT)

TIP

(HOT +)

SLEEVE

(GROUND)

HOT +

COLD –

SLEEVE

FROM SOURCE DEVICE (OUTPUT)

TO NEXT DEVICE (INPUT)

1/4” TS PHONE TO MALE XLR

1 2

3

HOT +

TIP

(HOT +)

SLEEVE

(GROUND)

SLEEVE

FROM SOURCE DEVICE (OUTPUT)

TO NEXT DEVICE (INPUT)

RCA PHONO TO MALE XLR

1 2

3

HOT +

TIP

(HOT +)

SLEEVE

(GROUND)

SLEEVE

RCA PHONO TO 1/4” TRS PHONE

FROM SOURCE DEVICE (OUTPUT)

HOT +

COLD –

SLEEVE

TIP

(HOT +)

SLEEVE

(GROUND)

RCA PHONO TO 1/4” TS PHONE

FROM SOURCE DEVICE (OUTPUT)

HOT +

SLEEVE

TIP

(HOT +)

SLEEVE

(GROUND)

FROM SOURCE DEVICE (OUTPUT)

TO NEXT DEVICE (INPUT)

FEMALE XLR TO 1/4” TRS PHONE

2 1

3

HOT +

TIP

(HOT +)

RING

(COLD –)

SLEEVE

(GROUND)

SLEEVE

COLD –

1/4” TRS PHONE TO MALE XLR

FROM SOURCE DEVICE (OUTPUT)

HOT +

TIP

(HOT +)

RING

(COLD –)

SLEEVE

(GROUND)

SLEEVE

COLD –

1/4” TRS PHONE TO TRS PHONE

FROM SOURCE DEVICE (OUTPUT)

TO NEXT DEVICE (INPUT)

TIP

(HOT +)

RING

(COLD –)

SLEEVE

(GROUND)

HOT +

TIP

(HOT +)

RING

(COLD –)

SLEEVE

(GROUND)

COLD –

SLEEVE

FROM SOURCE DEVICE (OUTPUT)

FEMALE XLR TO MALE XLR

2 1

3

HOT +

SLEEVE

COLD –

FROM SOURCE DEVICE (OUTPUT)

TO NEXT DEVICE (INPUT)

FEMALE XLR TO 1/4” TRS PHONE

2 1

3

HOT +

TIP

(HOT +)

RING

(COLD –)

SLEEVE

(GROUND)

SLEEVE

COLD –

1/4” TRS PHONE TO MALE XLR

FROM SOURCE DEVICE (OUTPUT)

HOT +

TIP

(HOT +)

RING

(COLD –)

SLEEVE

(GROUND)

SLEEVE

COLD –

FROM SOURCE DEVICE (OUTPUT)

FEMALE XLR TO MALE XLR

2 1

3

HOT +

SLEEVE

COLD –

1/4” TRS PHONE TO MALE XLR

FROM SOURCE DEVICE (OUTPUT)

TO NEXT DEVICE (INPUT)

1 2

3

HOT +

TIP

(HOT +)

RING

(COLD –)

SLEEVE

(GROUND)

SLEEVE

COLD –

Technical Information

Audio Cable Diagrams

FROM SOURCE DEVICE (OUTPUT)

TIP

(LEFT)

(GROUND)

RING

(RIGHT)

FROM SOURCE DEVICE (OUTPUT)

TIP

(HOT +)

FROM SOURCE DEVICE (OUTPUT)

RING

(COLD –)

TIP

(HOT +)

FROM SOURCE DEVICE (OUTPUT)

SLEEVE

(GROUND)

SLEEVE

(GROUND)

2 1

3

RIGHT

SLEEVE

LEFT

3.5 mm TRS MINI TO TRS MINI

1/4” TS PHONE TO TS PHONE

1/4” TRS PHONE TO TRS PHONE

COLD –

HOT +

SLEEVE

COLD –

HOT +

SLEEVE

TO NEXT DEVICE (INPUT)

SLEEVE

RING

(RIGHT)

(LEFT)

(GROUND)

TO NEXT DEVICE (INPUT)

SLEEVE

(GROUND)

TO NEXT DEVICE (INPUT)

SLEEVE

(GROUND)

TO NEXT DEVICE (INPUT)

1 2

3

RING

(COLD –)

TIP

(HOT +)

TIP

26

FEMALE XLR TO MALE XLR

Speciﬁcations

INPUTS

Mic/Line Number of Inputs: 2, independently switchable between mic or line level Connectors: Female ¼” - XLR combination Type: Electronically balanced, RF filtered Impedance: Switch set to MIC: 2 kΩ balanced, Switch set to LINE: 22 kΩ balanced Max Gain: Switch set to MIC: 48 dB, Switch set to LINE: 5 dB Max Input Level: Switch set to MIC: 0 dBu, Switch set to LINE: +20 dBu CMRR: > 45 dB

Aux Number of Inputs: 1 Connector: Female stereo 1/8” (3.5 mm) TRS mini Type: Unbalanced, RF filtered Impedance: 20 kΩ Max Input Level: +20 dBu

OUTPUTS

Number of Outputs: 2 line outputs Connectors: Male XLR Type: Impedance balanced, RF filtered Impedance: 40 Ω Max Output Level: +14 dBu

MIC/LINE A/D & D/A PERFORMANCE

Converters: 24-bit Dynamic Range: 115 dB A-weighted

AUX INPUT A/D PERFORMANCE

D/A Converter: 24-bit D/A Dynamic Range: 106 dB A-weighted

SYSTEM PERFORMANCE

Internal Processing Wordlength: 32-bit floating point Sample Rate: 48 kHz Dynamic Range: 103.5 dB A-weighted

102.5 dB unweighted THD+Noise: 0.04% typical at 0 dBu in/out, 1 kHz Frequency Response: 20 Hz – 20 kHz, +0 /- 0.5 dB Interchannel Crosstalk: < -80 dB, -84 dB typical Latency: Input to output: 3.4 ms

POWER SUPPLY

Model: PS0913DC-04 (9 VDC) Operating Voltage: 100-240 VAC, 50/60 Hz Power Consumption: 4.5 Watts (500 mA)

PHYSICAL

Unit Weight: 1.2 lbs. (0.54 kg) Shipping Weight: 2.04 lbs. (0.93 kg) Dimensions: 6.1” (L) x 4.1” (W) x 1.69” (H)

154.9 mm (L) x 104.1 mm (W) x 42.9 mm (H)

Specifications subject to change without notice.

27

Additional Resources

dbx Website

http://dbxpro.com

goRack Product Page

http://dbxpro.com/en-US/products/goRack

dbx Support

http://dbxpro.com/en-US/support

dbx User’s Forum

http://dbxpro.com/forum

28

Phone:

Website:

Support:

is a registered trademark of HARMAN

(801) 566-8800 dbxpro.com dbxpro.com/en-US/support

dbx Professional Products

goRack Owner’s Manual

5064543-C

dbx dbx GoRack dbx gorack

Specifications and Main Features

Frequently Asked Questions

User Manual

Overview

Introduction

Features

User Interface & Connectors

Top Panel

Rear Panel

Setup

Making Connections

Setting Initial System Levels

Operating The goRack

Master Volume

Output Limiter & Clipping

Anti-Feedback

Compressor

Subharmonic Synthesizer

Application Diagrams

Application 1: Speech/Presentation

Application 2: Solo Artist/Duo Performance

Application 3: Band Performance/DJ

Application 4: Using Powered Subwoofers

Technical Information

Audio Cable Diagrams

Additional Resources