SoundCraft GB4 User Manual

GB4 UserGB4 User

GB4 User

GB4 UserGB4 User
GuideGuide

Guide

GuideGuide

1GB4 User Guide

IMPORTANT

Please read this manual carefully before using

your mixer for the first time.

© Harman International Industries Ltd. 2004, 2005

All rights reserved

Parts of the design of this product may be protected by worldwide patents.

Part No. ZM0302-02

Soundcraft is a trading division of Harman International Industries Ltd. Information in this manual
is subject to change without notice and does not represent a commitment on the part of the
vendor. Soundcraft shall not be liable for any loss or damage whatsoever arising from the use of
information or any error contained in this manual.

No part of this manual may be reproduced, stored in a retrieval system, or transmitted, in any
form or by any means, electronic, electrical, mechanical, optical, chemical, including photocopying
and recording, for any purpose without the express written permission of Soundcraft.

Harman International Industries Limited
Cranborne House
Cranborne Road
POTTERS BAR
Hertfordshire
EN6 3JN
UK
Tel: [phone]
Fax: [phone]

http://www.soundcraft.com

2 GB4 User Guide

ContentsContents

Contents

ContentsContents

Introduction 5

Key Features 6
Warranty 7

Installation 9

SAFETY SYMBOL GUIDE 9
IMPORTANT SAFETY WARNINGS 10
Mains Installation 12
WORKING SAFELY WITH SOUND 14
Setting Up & Troubleshooting 14
Optional External Power Supply 16
Audio Connector Pinouts 17
Dimensions 18

Block Diagrams 19

Mono Input 20
Stereo Input 21
Talkback and Stereo Returns 22
Group/Aux/Matrix Outputs 23
Master Section 24

Using The Console 25

Mono Input 26
Stereo Input 28
Master Section 31
Rear Connector Panel 33

Specifications 35

Mark-up Sheets 37

3GB4 User Guide

NOTE: This equipment has been tested and found to comply with the limits for a Class A digital
device, pursuant to Part 15 of the FCC Rules. These limits are designed to provide reasonable
protection against harmful interference when the equipmentis operated in a commercial
environment. This equipment generates, uses and can radiate radio frequency energy and, if
not installed and used in accordance with the instruction manual, may cause harmful interference
to radio communications. Operation of this equipment in a residential area is likely to cause
harmful interference in which case the user will be required to correct the interference at his own
expense.

This Class A digital apparatus meets the requirements of the Canadian Interference-Causing
Equipment Regulations.

Cet appareil numérique de la Classe A respecte toutes les exigences du Règlement sur le
matériel brouilleur du Canada.

4 GB4 User Guide

IntrIntr

Intr

IntrIntr

oductionoduction

oduction

oductionoduction

5GB4 User Guide

Key Features

Thank you for buying the GB4 mixing console. its main features are:

Individually switched 48V phantom power on every mono input module.

8 Aux sends.

4 Group sends (paired).

4 Mute Groups.

7+4 Output Matrix.

Limiter on record output.

New GB30 mic pre-amp.

4-band GB30 EQ.

Integral power supply, with an external power supply link option.

All metal TRS jacks and Neutrik XLRs.

Direct outputs on all mono input channels.

6 GB4 User Guide

Warranty

1 Soundcraft is a trading division of Harman International Industries Ltd.

End User means the person who first puts the equipment into regular operation.
Dealer means the person other than Soundcraft (if any) from whom the End User
purchased the Equipment, provided such a person is authorised for this purpose by
Soundcraft or its accredited Distributor.
Equipment means the equipment supplied with this manual.

2 If within the period of twelve months from the date of delivery of the Equipment to

the End User it shall prove defective by reason only of faulty materials and/or
workmanship to such an extent that the effectiveness and/or usability thereof is
materially affected the Equipment or the defective component should be returned to
the Dealer or to Soundcraft and subject to the following conditions the Dealer or
Soundcraft will repair or replace the defective components. Any components
replaced will become the property of Soundcraft.

3 Any Equipment or component returned will be at the risk of the End User whilst in

transit (both to and from the Dealer or Soundcraft) and postage must be prepaid.

4 This warranty shall only be available if:

a) the Equipment has been properly installed in accordance with instructions
contained in Soundcraft's manual; and
b) the End User has notified Soundcraft or the Dealer within 14 days of the defect
appearing; and
c) no persons other than authorised representatives of Soundcraft or the Dealer have
effected any replacement of parts maintenance adjustments or repairs to the
Equipment; and
d) the End User has used the Equipment only for such purposes as Soundcraft
recommends, with only such operating supplies as meet Soundcraft's specifications
and otherwise in all respects in accordance Soundcraft's recommendations.

5 Defects arising as a result of the following are not covered by this Warranty: faulty or

negligent handling, chemical or electro-chemical or electrical influences, accidental
damage, Acts of God, neglect, deficiency in electrical power, air-conditioning or
humidity control.

6. The benefit of this Warranty may not be assigned by the End User.

7. End Users who are consumers should note their rights under this Warranty are in
addition to and do not affect any other rights to which they may be entitled against
the seller of the Equipment.

7GB4 User Guide

8 GB4 User Guide

InstallaInstalla

Installa

InstallaInstalla

tiontion

tion

tiontion

For your own safety and to avoid

invalidation of the warranty please

read this section carefully.

SAFETY SYMBOL GUIDE

For your own safety and to avoid invalidation of the warranty all text marked with these symbols
should be read carefully.

WARNINGS

The lightning flash with arrThe lightning flash with arr

The lightning flash with arr

The lightning flash with arrThe lightning flash with arr

intended to alerintended to aler

intended to aler

intended to alerintended to aler

insulated “dangerinsulated “danger

insulated “danger

insulated “dangerinsulated “danger

enclosurenclosur

enclosur

enclosurenclosur

constitute a risk of electric shock to persons.constitute a risk of electric shock to persons.

constitute a risk of electric shock to persons.

constitute a risk of electric shock to persons.constitute a risk of electric shock to persons.

The exclamation point within an equilateral triangleThe exclamation point within an equilateral triangle

The exclamation point within an equilateral triangle

The exclamation point within an equilateral triangleThe exclamation point within an equilateral triangle

is intended to aleris intended to aler

is intended to aler

is intended to aleris intended to aler

imporimpor

impor

imporimpor

instructions in the literaturinstructions in the literatur

instructions in the literatur

instructions in the literaturinstructions in the literatur

Contain imporContain impor

Contain impor

Contain imporContain impor

Contain imporContain impor

Contain impor

Contain imporContain impor

e that may be of sufe that may be of suf

e that may be of suf

e that may be of sufe that may be of suf

tant operating and maintenance (servicing)tant operating and maintenance (servicing)

tant operating and maintenance (servicing)

tant operating and maintenance (servicing)tant operating and maintenance (servicing)

the operation of your equipment.the operation of your equipment.

the operation of your equipment.

the operation of your equipment.the operation of your equipment.

HEADPHONES SAFETY WARNING

headphone outputs and monitoring levels.headphone outputs and monitoring levels.

headphone outputs and monitoring levels.

headphone outputs and monitoring levels.headphone outputs and monitoring levels.

t the user to the prt the user to the pr

t the user to the pr

t the user to the prt the user to the pr

ous voltage” within the prous voltage” within the pr

ous voltage” within the pr

ous voltage” within the prous voltage” within the pr

CAUTIONS

t the user to the prt the user to the pr

t the user to the pr

t the user to the prt the user to the pr

appliance.appliance.

appliance.

appliance.appliance.

NOTES

tant infortant infor

tant infor

tant infortant infor

tant infortant infor

tant infor

tant infortant infor

owhead symbol, isowhead symbol, is

owhead symbol, is

owhead symbol, isowhead symbol, is

esence of un-esence of un-

esence of un-

esence of un-esence of un-

oduct’soduct’s

oduct’s

oduct’soduct’s

ficient magnitude toficient magnitude to

ficient magnitude to

ficient magnitude toficient magnitude to

esence ofesence of

esence of

esence ofesence of

e accompanying thee accompanying the

e accompanying the

e accompanying thee accompanying the

mation and useful tips onmation and useful tips on

mation and useful tips on

mation and useful tips onmation and useful tips on

mation and useful tips onmation and useful tips on

mation and useful tips on

mation and useful tips onmation and useful tips on

9GB4 User Guide

IMPORTANT SAFETY WARNINGS

THIS UNIT MUST BE EARTHED

Under no circumstances should the mains earth be disconnected from the mains

lead.

The wires in the mains lead are coloured in accordance with the following code:

Earth: Green and Yellow (Green/Yellow - US)

Neutral: Blue (White - US)

Live: Brown (Black - US)

As the colours of the wires in the mains lead may not correspond with the coloured markings identifying the terminals in your plug,
proceed as follows:

The wire which is coloured Green and Yellow must be connected to the terminal in the plug which is marked with

the letter E or by the earth symbol.

The wire which is coloured Blue must be connected to the terminal in the plug which is marked with the letter N.

The wire which is coloured Brown must be connected to the terminal in the plug which is marked with the letter L.

Ensure that these colour codings are followed carefully in the event of the plug being changed.

To avoid the risk of fire, replace the mains fuse only with the correct value fuse,

as marked on the rear panel.

The internal power supply unit contains no user serviceable parts. Refer all

servicing to a qualified service engineer, through the appropriate Soundcraft

dealer.

10 GB4 User Guide

WARNINGS

• Read these instructions.

• Keep these instructions.

• Heed all warnings.

• Follow all instructions.

• This unit contains no user serviceable parts. Refer all servicing to a qualified service engineer,

through the appropriate Soundcraft dealer.

• Clean the apparatus only with a dry cloth.

• Do not install near any heat sources such as radiators, heat resistors, stoves, or other apparatus

(including amplifiers) that produce heat.

• Do not block any ventilation openings. Ventilation should not be impeded by covering the

ventilation openings with items such as newspapers, table cloths, curtains etc. Install in
accordance with the manufacturer’s instructions.

• Do not use this apparatus near water. The apparatus must not be exposed to dripping or

splashing. Objects containing liquid must not be placed on the apparatus.

• The disconnect device is the mains plug; it must remain accessible so as to be readily operable

in use.

• 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.

• Protect the power cord from being walked on or pinched particularly at plugs, convenience

receptacles and the point where they exit from the apparatus.

• Only use cables and hardware specified by the manufacturer.

• Unplug this apparatus during lightning storms or when unused for long periods of time.

• Refer all servicing to qualified service personnel. Servicing is required when the apparatus 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 apparatus, the apparatus has been exposed
to rain or moisture, does not operate normally or has been dropped.

• It is recommended that all maintenance and service on the product should be carried out by

Soundcraft or its authorised agents. Soundcraft cannot accept any liability whatsoever
for any loss or damage caused by service, maintenance or repair by unauthorised
personnel.

• If a trolley is used to carry this apparatus, use caution when moving the trolley / apparatus

combination to avoid injury from tip-over.

• No naked flame sources, such as lighted candles or cigarettes etc., should be placed on the

apparatus.

• Warning: To reduce the risk of fire or electric shock, do not expose this apparatus to rain or

moisture. Do not expose the apparatus to dripping or splashing and do not place objects
filled with liquids, such as vases, on the apparatus.

11GB4 User Guide

General Precautions

Avoid storing or using the mixing console in conditions of excessive heat or cold, or in positions where it is likely to be subject to
vibration, dust or moisture. Do not use any liquids to clean the fascia of the unit: a soft dry cloth is ideal.

Avoid using the console close to strong sources of electromagnetic radiation (e.g. video monitors, high-power electric cabling): this
may cause degradation of the audio quality due to induced voltages in connecting leads and chassis.

Caution! In all cases, refer servicing to qualified personnel.

Handling and Transport

The console is supplied in a strong carton. If it is necessary to move it any distance after installation it is recommended that this
packing is used to protect it. Be sure to disconnect all cabling before moving. If the console is to be regularly moved we recommend
that it is installed in a foam lined flightcase. At all times avoid applying excessive force to any knobs, switches or connectors.

Power Cable

Always use the power supply cable supplied with the mixer: the use of alternative cables may cause damage and voids the warranty.

W a r n i n g ! In the event of an electrical storm, or large mains voltage

fluctuations, immediately switch off the mixer and unplug from the mains.

Signal Levels

It is important to supply the correct input levels to the console, otherwise signal to noise ratio or distortion performance may be
degraded; and in extreme cases, damage to the internal) circuitry may result. Likewise, on all balanced inputs avoid sources with
large common mode DC, AC or RF voltages, as these will reduce the available signal range on the inputs. Note that OdBu =0.775V
RMS.

Refer to the Specifications section for details of input and output levels.

Mains Installation

General Wiring Procedures

To take full advantage of the excellent signal to noise ratio and low distortion of Soundcraft consoles, care must be taken to ensure
that incorrect installation and wiring does not degrade the performance of the desk. Hum, buzz, instability and Radio Frequency
interference can usually be traced to earth loops and inferior earthing systems. In some areas, especially heavily industrial areas,
the incoming mains earth will not be adequate and a separate technical earth for all the audio equipment must be supplied.
However, check with your local electricity supply company to ensure that safety regulations are not infringed or negated.

The successful, hum free, installation of a system requires forethought, and the establishment of a set of ground rules, which must
be consistently adhered to at all stages of installation.

12 GB4 User Guide

Initial Wiring Considerations

For optimum performance, it is essential for the earthing system to be clean and noise free, as all signals are referenced to this
earth. A central point should be decided on for the main earth point system, and all earths should be 'star fed' from this point. It is
common electrical practice to `daisy chain' the earths to all electrical outlets but this method is unsuitable for audio installations. The
preferred method is to run an individual earth wire from each outlet, back to the system star point to provide a safety earth screen
reference for each piece of equipment.A separate earth wire should also be run from each equipment rack and area, to the star
point. This may or may not be used depending on circumstances, but it is easier to install in the first place, than later when problems
arise.The location of the star point should be a convenient, easily accessible place, preferably at the rear of the console or in the
main equipment rack.

Install separate 'clean' and 'dirty' mains outlets, wired individually back to the incoming mains distribution box. Use the 'clean' supply
for all audio equipment and the `dirty' supply for all lighting, etc. Never mix the two systems.

If necessary, to provide sufficient isolation from mains borne interference, install an isolating transformer. This should be provided
with a Faraday Shield which must be connected with earth.

Never locate the incoming mains distribution box near audio equipment, especially tape recorders, which are very sensitive to
electro-magnetic fields.

Ensure that all equipment racks are connected to earth, via a separate wire back to the star point.

Equipment which has unbalanced inputs and outputs may need to be isolated from the rack to prevent earth loops.

Audio Wiring

Having provided all equipment with power and earthing connections, consideration must be given to the method of providing audio
interconnection and adequate screening of those interconnections. This must be done in a logical sequence to avoid problems and
assist in the localisation of problem equipment.

Connect the FOH or Monitor system to the console and check for any hum, buzz, or RFI. Only when you are satisfied with the
quietness of the console and the PA system should you proceed with the next step.

Connect stereo or multitracktape recorders, FX and foldback sends one at a time, checking and isolating any connection which
degrades performance.

Connect all other peripheral devices.

Connect all microphone lines.

By following this sequence much time and future trouble will be saved, and the result will be a quiet, stable system.

Shielding

Audio equipment is supplied with a variety of input and output configurations, which must be taken into consideration when deciding
where the screen connections should be made. There are three sources of unwanted signal being impressed on the screen, which
are as follows:

Extraneous electrostatic or electromagnetic fields.

Noise and interference on the earth line.

Capacitive coupling between the screen and signal wires.

To minimise the adverse affects of the unwanted coupling to the signal wires, it is important that the screen is connected at one end
only, i.e. the screen must not carry any signal) current. Any signal) on the wires within the screen will be capacitively coupled to the
screen. This current will ultimately be returned to the source of the signal, either directly, if the screen is connected at the signal
source end, or indirectly via the earthing system, if the signal is connected at the signal destination end. The indirect connection will
cause an increase in high frequency cross-talk, and should be avoided wherever possible.

Therefore, in general, always connect the shield only at the signal source end. In high RF areas, the screen can also be connected
to earth via a 0.01 mF capacitor. This will present a short circuit at RF frequencies, thus lowering the effective shield impedance to
ground. However, at low audio frequencies the reactance of the capacitor will be sufficiently high not to cause an earth loop problem.

13GB4 User Guide

Points to Remember

In all cases, use good quality twin screened audio cable. Check for instability at the output.

Always connect both conductors at both ends, and ensure that the screen is only connected at one end.

Do not disconnect the mains earth from each piece of equipment. This is needed to provide both safety and screen returns to the
system star point.

Equipment which has balanced inputs and outputs may need to be electrically isolated from the equipment rack and/or other
equipment, to avoid earth loops.

It is important to remember that all equipment which is connected to the mains is a potential source of hum and interference and may
radiate both electrostatic or electromagnetic radiation. In addition, the mains will also act as a carrier for many forms of RF interference
generated by electric motors, air-conditioning units, thyristor light dimmers etc. Unless the earth system is clean, all attempts to
improve hum noise levels will be futile. In extreme cases there will be no alternative but to provide a completely separate and
independent `technical earth' to replace the incoming 'noisy earth'. However, always consult your local electricity supply authority to
ensure that safety regulations are not being infringed.

WORKING SAFELY WITH SOUND

Although your new console will not make any noise until you feed it signals, it has the capability to produce sounds which when
monitored through an amplifier or headphones can damage hearing over time.

The table below is taken from the Occupational Safety & Health Administration directive on Occupational noise exposure (1926.52):

PERMISSABLE NOISE EXPOSURE

DURATION PER DAY, HOURS SOUND LEVEL dBA SLOW RESPONSE

890
692
495
397
2 100

1.5 102
1 105

0.5 110
<0.25 115

Conforming to this directive will minimise the risk of hearing damage caused by long listening periods. A simple rule to follow is the
longer you listen the lower the average volume should be.

Please take care when working with your audio - if you are manipulating controls which you don’t understand (which we all do when
we are learning), make sure your monitors are turned down. Remember that your ears are the most important tool of your trade, look
after them, and they will look after you.

Most importantly - don’t be afraid to experiment to find out how each parameter affects the sound - this will extend your creativity and
help you to get the best results.

Recommended headphone impedance is 200-600 ohms.Recommended headphone impedance is 200-600 ohms.

Recommended headphone impedance is 200-600 ohms.

Recommended headphone impedance is 200-600 ohms.Recommended headphone impedance is 200-600 ohms.

14 GB4 User Guide

Setting Up & Troubleshooting

Initial set-up

Once you have connected up your system (see the sections on connection and wiring earlier in this manual for guidance) you are
ready to set initial positions for the controls on your mixer.

Set up individual input channel as follows:

Connect your sources (microphone, keyboard etc.) to the required inputs and release the MUTE switches. Note: Phantom
powered mics should be connected before the 48V is switched on.

Set Master faders at 0, input faders at 0, route the channels to MIX and set power amplifier level to suit the application.

Provide a typical performance level signal and press the PFL button on the first channel, monitoring the level on the
bargraph meters.

Adjust the input gain until the meter display is in the amber section, with occasional peaks to the first red LED at a typical
maximum source level. This allows sufficient headroom to accommodate peaks and establishes the maximum level for
normal operation (but see note below).

Repeat this procedure on other channels as required.

Listen carefully for the characteristic sound of `feedback’. If you cannot achieve satisfactory input level setting without
feedback, check microphone and speaker placement and repeat the exercise. If feedback persists, it may be necessary to
use a Graphic Equaliser to reduce the system response at particular resonant frequencies.

Note: The initial settings should only be regarded as a starting point for your mix. It is important to remember that many factors
affect the sound during a live performance, for instance the channel EQ settings or even the size of the audience!

You are now ready to start building the mix and this should be done progressively, listening carefully for each component in the mix
and watching the meters for any hint of overload. If this occurs, back off the appropriate Channel Fader slightly until the level is out
of the red segments, or adjust the Mix Master Faders. This procedure will ensure that the mixer is set up correctly, with adequate
headroom. If more amplification is needed, adjust the power amplifier level controls.

Troubleshooting

No PNo P

oo

ww

No P

No PNo P

Condenser Mic NoCondenser Mic No

Condenser Mic No

Condenser Mic NoCondenser Mic No

erer

o

w

er

oo

ww

erer

Is the mains supply present?

Is the mains lead firmly connected?

Check the mains fusing

If only one of the power indicators is illuminated, consult your Soundcraft dealer

t Wt W

oror

kingking

t W

or

king

t Wt W

oror

kingking

Is the 48V turned on?

Is the mic plugged into the Mic input?

Is the mic cable a balanced 3-wire type?

15GB4 User Guide

MeMe

tt

erer

s nos no

t shot sho

Me

t

er

s no

MeMe

tt

erer

s nos no

Has the input gain been set correctly? (see above.)

Is the source connected to the appropriate input socket for the level of signal?

Do you have something connecetd on the Inserts, and is that external device switched on?

Are the Master faders set at max., are input faders set high enough and is the channel routed to the output being monitored?

Is the MUTE switch released on the relevant channels?

Is the appropriate monitor select switch pressed?

Is there a PFL/AFL pressed on another channel?

No Mix outputNo Mix output

No Mix output

No Mix outputNo Mix output

Check that the Mix Master Fader is up?

t sho

t shot sho

wing anwing an

wing an

wing anwing an

y signaly signal

y signal

y signaly signal

No MonitNo Monit

No Monit

No MonitNo Monit

Headphones DistHeadphones Dist

Headphones Dist

Headphones DistHeadphones Dist

or outputor output

or output

or outputor output

Is a headphone jack plugged in?

Are the Monitor + Phones controls set high enough?

Is the appropriate monitor select switch pressed?

oror

tingting

or

ting

oror

tingting

Are the headphones less than 200Ω impedance?

Is the Phones level set too high?

Optional External Power Supply

Although the GB4 has its own internal power supply, an external backup power supply (DPS-3) can be connected to provide a
backup power supply. There is a dedicated connector on the rear connector panel.

16 GB4 User Guide

Audio Connector Pinouts

17GB4 User Guide

Dimensions

18 GB4 User Guide

BlocBloc

Bloc

BlocBloc

k Diak Dia

k Dia

k Diak Dia

gg

g

gg

rr

amsams

r

ams

rr

amsams

19GB4 User Guide

Mono Input

20 GB4 User Guide

Stereo Input

MUTES 1-4

PFL/EN

MATRIX 1-4

GRP 1-4

RIGHT

CENTRE

LEFT

AUX 5-8 PST
AUX 5-8 PRE

AUX 1-4

AUX1

AUX2

AUX3

AUX4

AUX5_PRE

AUX5_PST

AUX6_PRE

AUX6_PST

AUX7_PRE

AUX7_PST

AUX8_PRE

AUX8_PST

GAIN

ALL AUX SENDS

60dB

HAVE UNITY

0dBu

+48

-3dBu 0dBu

-3dBu

+13dB

MUTE

BLOCK

WITH

PFL

MUTE SW

+16

PEAK

+3dB

FDR

+3dB

MUTE

& GROUP

SWITCHES

BAL

0

+8

RECTIFIER

READING

AS ON

-10

INPUT

MONO

L-R 1-2 3-4

+13dB

C

GAIN LINE UP

-5dB FROM TOP

10dB

+48v

LF

LMID

HMID

HF

EQ

0dBu

-15dB -15dB

+15dB +15dB

-15dB

+15dB

-15dB

+15dB

MONO

LR

PEAK

DETECT

0dBu

HF LMIDHMID LF

0dBu

STEREO INPUT

1

3

MIC

2

CHASS

LINE

CHASS

1

3

MIC

PUSH

2

CHASS

LINE

CHASS

21GB4 User Guide

Talkback and Stereo Returns

MUTES 1-4

PFL/EN

MATRIX 1-4

GRP 1-4

RIGHT

CENTRE

LEFT

AUX 5-8 PST
AUX 5-8 PRE

AUX 1-4

TALKBACK

GROUPS AUX1-2 AUX 3-4 AUX 5-6 AUX 7-8

+38dB

LEVEL

TALKBACK

TB MIC

PUSH

OFF

1

2

GRP1 BUS

RET 1

LEVEL

0dBu

3

CHASS

STE RET 1

STEREO RETURNS

L MIX BUS

0dBu

L

1-2

8dB GAIN

L-R

AT T OP

CHASS

GRP2 BUS

R MIX BUS

CHASS

R

RET 2

GRP3 BUS

LEVEL

STE RET 2

L MIX BUS

L

3-4

L-R

CHASS

GRP4 BUS

R MIX BUS

CHASS

R

22 GB4 User Guide

Group/Aux/Matrix Outputs

23GB4 User Guide

Master Section

24 GB4 User Guide

Using Using

Using

Using Using

TT

he Consolehe Console

T

he Console

TT

he Consolehe Console

25GB4 User Guide

Mono Input

12

10

5

0

5

10

15

20

30

MIC
GAIN

LINE

-20

HF

HI
MID

LO
MID

LF

AUX1

PRE

AUX2

PRE

AUX3

PRE

AUX4

PRE

AUX5

PRE
POST

AUX6

PRE
POST

AUX7

PRE
POST

AUX8

PRE
POST

PAN

=

100Hz

6

9

12

550

6

9

12

6

9

12

6

9

12

1

48V

30

5

-

+

0

15

3k

-

+

0

15

450

80 1.9k

-

+

0

15

-

+

0

15

EQEQ

0

L

+16

+8

-10

MIC GAIN (1) adjusts the sensitivity of both mic (XLR) and Line (1/4” jack) inputs. Both inputs

3
4

PK

1

60dB

5

33

6

9

12

15

are electronically balanced, and are located on the rear connector panel.

The PEAK LED (2), monitors two points in the audio path: pre-insert point and post-EQ.

2

The 48V switch (3) applies 48V phantom power to the input XLR. An adjacent LED indicates
when the phantom power is on.

The PHASE switch (4) reverses the phase of the selected input.

HI-PASS (5) switches in the high-pass filter.

13k
33

6

9

12

15

6

The module insert point is pre-EQ , pre-fader. It is located on the rear connector panel.

The EQ section (6) is four band, with shelving HF and LF, and swept peaking high and low mid
sections.

33

6

9

12

15

33

6

9

12

15

7

0

+

6

0

+

6

0

+

6

0

+

6

8

0

+

6

0

+

6

0

+

6

0

+

6

9

R

MUTE

The HF and LF sections give +/-15dB cut/boost at 12kHz and 60Hz respectively. The Lo-mid
section gives +/-15dB cut/boost at 80Hz-1.9kHz. The Hi-mid section gives +/-15dB cut/boost at
550Hz-13kHz.

The section is switched in by the EQ switch (7).

Signal is sent to the AUX 1-8 busses via individual level pots (8). Aux 1- 4 are pre fader signals,
whilst Aux 5-8 are globally selectable pre or post fade via switches on the master section.

Signal for the L+R (main mix), 1-2 group busses and 3-4 group busses are routed via the PAN
pot (9). The pan pot positions the signal within the stereo image.

The signal in the module is turned on and off by the illuminated MUTE switch (10), and also the
master mutes M1-M4 from the master section, if they are selected using the M1 - M4 switches
(11).

Post-fader signal level is controlled by a 100mm fader (12).

The signal is sent to the stereo mix bus, centre bus and 4 group busses using the C, L+R, 1-2
and 3-4 switches (13). Note the use of group 1 & 2, and group 3 & 4 as 2 sets of stereo pairs.

A 4-segment LED bargraph meter (14), next to the fader, meters the signal post-EQ, pre-mute,
pre-fade. The meter has a peak type response.

The PFL switch (15) feeds the pre-mute, pre-fade signal to the monitor output and phones
output. An adjacent LED indicates when the PFL is on.

10

C

L
R

13

1
2

3
4

14

0

M

1

M

11

2

M

3

M

4

15

PFL

1

26 GB4 User Guide

LINE

MIC

INS

DIR

PRE

1

Rear Connectors

INSERT (1/4" TRS Jack)

Tip Send Signal
Ring Return Signal
Sleeve Ground

LINE INPUT (1/4" TRS Jack)

Tip Signal Hot
Ring Signal Cold
Sleeve Ground

MIC INPUT (3 pin female XLR)

Pin 1 Ground
Pin 2 Signal Hot
Pin 3 Signal Cold

DIRECT OUTPUT (1/4" TRS Jack)“

Tip Signal Hot
Ring Signal Cold
Sleeve Chassis

The DIRECT OUTPUT is normally post fader. Pressing the PRE button switches it to pre-EQ,
pre-mute, pre-fader.

27GB4 User Guide

Stereo Input

12

STE1

48V

L

STE
MIC
GAIN

3
4

PK

30

1

5

60dB

=

LINE

-20

L

MONO

HF

6

9

12

15

HM

6

9

12

15

LM

6

9

12

15

LF

6

9

12

15

AUX1

PRE

AUX2

PRE

AUX3

PRE

AUX4

PRE

AUX5

PRE
POST

AUX6

PRE
POST

AUX7

PRE
POST

AUX8

PRE
POST

BAL

L

5

R

-

+

0

33

6

9

12

15

-

+

0

33

6

6

9

12

15

-

+

0

33

6

9

12

15

-

+

0

33

6

9

12

15

EQ

7

0

+

6

0

+

6

0

+

6

0

+

6

8

0

+

6

0

+

6

0

+

6

0

+

6

0

9

R

MUTE

10

10

5

0

5

10

15

20

30

C

L
R

13

1
2

3
4

+16

+8

14

0

-10

M
1

M

11

2

M
3

M
4

15

PFL

STE MIC GAIN (1) adjusts the sensitivity of both pairs of Mic (XLRs) or Line (1/4" jacks) inputs.
Both pairs are electronically balanced, and are located on the rear connector panel.

The PEAK LED (2), monitors both left and right signals after the gain control.

2

The 48V switch (3) applies 48V phantom power to the input XLRs. An adjacent LED indicates
when the phantom power is on.

The Left PHASE switch (4) inverts the phase of the left channel.

The L switch (5) routes the left input signal to both L and R channels in the module. The R switch
similarly routes the right input signal. Pressing L and R together mono sums the input.

The EQ section (6) is four band, with shelving high and low frequencies and peaking high-mid
and low-mid bands.

The HF control gives +/-15dB cut/boost at 12KHz. The LF control gives +/-15dB cut/boost at
60Hz. The HM control gives +/-15dB cut/boost at a centre frequency of 2.5kHz, and the LM
control gives +/-15dB cut/boost at a centre frequency of 450Hz.

The EQ is switched in by the EQ switch (7).

A mono sum of the signal is sent to the AUX 1-8 busses via individual level pots (8). Aux 1- 4 are
pre fader signals, whilst Aux 5-8 are globally selectable pre or post fade via switches on the
master section.

The BAL control (9) allows the stereo image to be balanced between the left and right channels
within the module.

The stereo signal in the module is turned on and off by the illuminated MUTE switch (10), and
also the master mutes M1-M4 from the master section, if they are selected using the M1 - M4
switches (11).

Post-fader signal level is controlled by a 100mm stereo fader (12).

The signal is sent to the stereo mix bus, centre bus and 4 group busses using the C, L+R, 1-2
and 3-4 switches (13). Note the use of group 1 & 2, and group 3 & 4 as 2 sets of stereo pairs.
The feed to the centre bus is a mono sum of the stereo signal.

A 4-segment LED bargraph meter (14), next to the fader, meters the signal post-EQ, pre-mute,
pre-fade. The meter has a peak type response.

The PFL switch (15) feeds a mono sum of the pre-mute, pre-fade signal to the monitor output
and phones output. An adjacent LED indicates when the PFL is on.

STE1

28 GB4 User Guide

MIC L

MIC R

LINE

R

STE1

L

Rear Connectors

MIC INPUT LEFT and RIGHT (3 pin female XLR)

Pin 1 Ground
Pin 2 Signal Hot
Pin 3 Signal Cold

LINE INPUT LEFT and RIGHT (1/4" TRS Jacks)

Tip Signal Hot
Ring Signal Cold
Sleeve Ground

29GB4 User Guide

30
31

3

14

15
11

12

13

10

8

9

1

6
5

7

17

23

21
35

22
37

39
24
36
38
33
40
32

29
27

26
28

41

34

25

4

2

19
18

20

16

30 GB4 User Guide

Master Section

GROUPS

Note that the group controls are swappable with the aux 1-4 controls by pressing the GRP/AUX
SWAP switches (1). If the contols are swapped the aux and group faders swap function (and
their respective AFL buttons) and the group insert point becomes an aux insert point. The 12­segment meter swaps function.The group and aux output connectors retain their original function.

The following description assumes that swap mode is NOT used.

The GRPx fader (2) controls the level after the insert point. This signal is fed to the Group Output
XLR on the rear connector panel.

The 12-segment meter (3) monitors the level after the fader.

The AFL button (4) feeds the group post-fader signal to the monitor output and phones output.

The post-fader signal is routed to the main mix stereo pair via the L-R switch (5) and the centre
mix via the C switch (6). The Group PAN pot (7) is before the L-R switch in the signal path. It is
used to position the group’s signal within the stereo image of the main mix.

The post-fader signal may be routed to any or all of the 4 matrix busses via the four matrix input
pots (8).

AUX MASTERS 1-4

Aux masters 1-4 are all pre-fade feeds from the input modules.

Each AUX master 1-4 level pot (9) controls the level fed from its own aux bus to its aux output.

The AFL button (10) feeds the aux post-fader signal to the monitor output and phones output.

AUX MASTERS 5-8

Aux masters 5-8 are each globally selectable to be pre-fade or post-fade feeds. this is done via
the PRE (11) switch.

Each AUX master 5-8 level pot (12) controls the level fed from its own aux bus to its aux output.

The AFL button (13) feeds the aux post-fader signal to the monitor output and phones output.

MATRIX MASTERS

Each MTX MASTER level pot (14) controls the level fed from its own matrix bus to its matrix
output.

The AFL button (15) feeds the matrix master post-fader signal to the monitor output and phones
output.

31GB4 User Guide

L, R & C Outputs

Each of the 3 main mix busses, Left, Right and Centre, has its own insert point. These are
located on the rear connector panel. Each mix bus has its own Fader (16) following the insert
point in the signal path.

The post-fader signal for each bus is then routed to the following places:

• its main output XLR on the rear connector panel,

• feeds to the matrix 1- 4 buses (17),

• the REC/ALT output section,

• the MONITOR SOURCE select switches L-R (18) and C (19).

A mono sum of the L & R outputs can be routed to the C output via the L-R TO CENTRE switch
(20).

REC/ALT Outputs

The REC/ALT output is a stereo pair. Each of the 2 channels (L & R) has 2 output connectors on
the rear connector panel: an RCA phono socket and a 1/4” jack.

The three feeds to the REC/ALT section are from the L, R & C main faders (16). The C switch
(21) feeds the C signal to both L & R channels. The MONO switch (22) sums both the left and
right channels together.

The LEVEL pot (23) feeds the stereo signal to a limiter which can be enabled by the LIMITER
ON switch (24), the adjacent LED indicates when the limiter is active.

The stereo signal is then fed to the rear connector panel.

Monitoring & PFL

The monitor section feeds the control room L & R outputs (on the rear connector panel) and the
headphones output (right hand front of console).

The sources for the monitor section are:

• the 2-track input (25), its volume is controlled by the 2-TRK LEVEL control (26),

• the centre mix, C (19), and

• the main mix, L-R (18).

Any or all of these sources may be selected at any one time. The monitor signals (L & R) are
passed to the control room L & R outputs via the C/ROOM level pot (27), and to the headphones
socket via the H/PHONES pot (28). The monitor L & R signals can be mono summed using the
MNO switch (29).

The L & R 12-segment meters (30) indicate the level of the monitored signal, as selected by the
monitor source select switches. The CENTRE meter (31) monitors the Centre mix output except
when any AFL or PFL button is pressed.

When a PFL or AFL button is pressed the CENTRE meter displays the pfl/afl signal level, and
the pfl/afl signal is routed to the control room outputs and to the headphones. This signal replaces
the normal monitor signal. The PFL/AFL LED (32) illuminates when this is happening.

Note: the 2-track input may also be routed directly to the main L-R mix via the 2 TRK TO MIX
switch (33).

Master Mutes

These four switches (34) will mute any input modules which have been assigned to them.

32 GB4 User Guide

Talkback

The talkback mic input is on the rear connector panel.

The level of the talkback mic signal is controlled by the LEVEL pot (35). The signal is the fed to
all groups, aux 1-2, aux 3-4, aux 5-6 and aux 7-8 using the appropriate buttons (36).

Stereo Returns

There are two stereo return channels. The connectors are 1/4” jacks on the rear connector
panel.

Each has its own level control (37), and each may be routed to the L-R main mix or to groups 1­2 for Stereo Return 1 or to groups 3-4 for Stereo Return 2 via the appropriate switches (38).

PSU Monitor LEDs

These LEDS (39) confirm the presence of the correct voltage on the +48V and the +/-17V power

rails in the console.

Rear Connector Panel

INSINSINSINS

T/B MIC

R MNTR

L

2 TRK IN

R

MTX4

RR

L

L

R

MTX3

REC/ALT

OUT

L

R

T/B MIC (3-pin female XLR)

Pin 1 Ground
Pin 2 Signal Hot
Pin 3 Signal Cold

GRP 1GRP 3MIX LMIX C

INS INS INS

MIX R GRP 4 GRP 2

AUX4

AUX8L L AUX7

AUX3MTX2

AUX2MTX1

AUX6

AUX1

AUX5STE RTN2 STE RTN1

MIX L, R & C OUTPUTS (3-pin male XLRs)

Pin 1 Chassis
Pin 2 Signal Hot
Pin 3 Signal Cold

33GB4 User Guide

MIX L, R & C INSERT POINTS (1/4” TRS Jacks)

Tip Send Signal
Ring Return Signal
Sleeve Chassis

L & R MONITOR OUTPUTS (1/4” TRS Jacks)

Tip Signal Hot
Ring Signal Cold
Sleeve Chassis

GROUP 1-4 OUTPUTS (3-pin male XLRs)

Pin 1 Chassis
Pin 2 Signal Hot
Pin 3 Signal Cold

GROUP 1-4 INSERT POINTS (1/4” TRS Jacks)

Tip Send Signal
Ring Return Signal
Sleeve Chassis

AUX 1-8 OUTPUTS (1/4” TRS Jacks)

Tip Signal Hot
Ring Signal Cold
Sleeve Chassis

MATRIX 1-4 OUTPUTS (1/4” TRS Jacks)

Tip Signal Hot
Ring Signal Cold
Sleeve Chassis

REC/ALT OUTPUTS (1/4” TRS Jacks and RCA Phonos)

JACK
Tip Signal Hot
Ring Signal Cold
Sleeve Chassis

PHONO
Centre Signal
Screen Chassis

2-TRACK INPUTS (RCA Phono)

Centre Signal
Screen Chassis

STEREO RETURN 1 & 2 INPUTS (1/4” TRS Jacks)

Tip Signal Hot
Ring Signal Cold
Sleeve Chassis

34 GB4 User Guide

TYPICAL SPECIFICATYPICAL SPECIFICA

TYPICAL SPECIFICA

TYPICAL SPECIFICATYPICAL SPECIFICA

Noise

Measured RMS, 22Hz to 22kHz Bandwidth
Mic E.I.N. @ unity gain,150Ω source impedance -128dBu
Mix Output, 40 inputs routed to mix <-82dBu
Group Outputs <-83dBu
Aux Outputs <-80dBu
Matrix Outputs <-89dBu

Crosstalk (@1kHz, typical)

Input Channel Mute <-97dB
Input Fader cut-off <-95dB
Pan isolation <-77dB
Mix route isolation <-97dB
Group route isolation <-97dB
Adjacent channel crosstalk <-99dB
Group to Mix <-89dB
Aux Send pots offness (typical) <-84dB
Matrix Send pots offness (typical) <-89dB

Frequency Response

Mic/Line Input to any output, 20Hz - 20kHz <1dB

THD + N

Mic sens. -30dBu, +20dBu at all outputs @1kHz <0.006%

CMRR

Typical @ 1kHz 80dB

Input & Output Max Levels

Mono & Stereo Mic Inputs +15dBu
Mono & Stereo Line Inputs +30dBu
Stereo Returns & Insert Returns +20dBu
Any output +20dBu
Nominal Operating Level 0dBu
Headphone Power 2x250mW into 200Ω

Input & Output Impedances

Mic Inputs 2kΩ
Line Inputs and Stereo Returns 10kΩ
Input channels Insert Return 5kΩ with EQ in, otherwise 3kΩ
Mix, Group, Aux, Matrix & Direct outputs 150Ω
Insert sends 75Ω
Recommended Headphone Impedance 50 - 600Ω

TIONSTIONS

TIONS

TIONSTIONS

35GB4 User Guide

36 GB4 User Guide

MarMar

Mar

MarMar

k-up Sheetsk-up Sheets

k-up Sheets

k-up Sheetsk-up Sheets

37GB4 User Guide

1

48V

1

48V

1

48V

1

48V

1

48V

1

48V

1

48V

1

48V

MIC
GAIN

LINE

HF

HI
MID

LO
MID

LF

AUX1

PRE

AUX2

PRE

AUX3

PRE

AUX4

PRE

AUX5

PRE
POST

AUX6

PRE
POST

AUX7

PRE
POST

AUX8

PRE
POST

PAN

-20

5

=

100Hz

6

9

12

15

550

6

9

12

15

80 1.9k

6

9

12

15

6

9

12

15

30

60dB

-

+

0

33

15

3k

13k

-

+

0

33

15

450

-

+

0

33

15

-

+

0

33

15

EQEQ

+

6

+

6

+

6

+

6

+

6

+

6

+

6

+

6

0

30

MIC

PK

GAIN

5

60dB

=

LINE

-20

100Hz

-

+

0

33

HF

6

6

9

9

12

12

15

15

3k

13k

550

HI

-

+

0

MID

33

6

6

9

9

12

12

15

15

450

LO

80 1.9k

MID

-

+

0

33

6

6

9

9

12

12

15

15

-

+

0

33

LF

6

6

9

9

12

12

15

15

EQEQ

AUX1

0

PRE

+

6

AUX2

0

PRE

+

6

AUX3

0

PRE

+

6

AUX4

0

PRE

+

6

AUX5

PRE

0

POST

+

6

AUX6

PRE

0

POST

+

6

AUX7

PRE

0

POST

+

6

AUX8

PRE

0

POST

+

6

0

PAN

30

MIC

PK

GAIN

5

60dB

=

LINE

-20

100Hz

-

+

0

33

HF

6

6

9

9

12

12

15

15

3k

13k

550

HI

-

+

0

MID

33

6

6

9

9

12

12

15

15

450

LO

80 1.9k

MID

-

+

0

33

6

6

9

9

12

12

15

15

-

+

0

33

LF

6

6

9

9

12

12

15

15

EQEQ

AUX1

0

PRE

+

6

AUX2

0

PRE

+

6

AUX3

0

PRE

+

6

AUX4

0

PRE

+

6

AUX5

PRE

0

POST

+

6

AUX6

PRE

0

POST

+

6

AUX7

PRE

0

POST

+

6

AUX8

PRE

0

POST

+

6

0

PAN

30

MIC

PK

GAIN

5

60dB

=

LINE

-20

100Hz

-

+

0

33

HF

6

6

9

9

12

12

15

15

3k

13k

550

HI

-

+

0

MID

33

6

6

9

9

12

12

15

15

450

LO

80 1.9k

MID

-

+

0

33

6

6

9

9

12

12

15

15

-

+

0

33

LF

6

6

9

9

12

12

15

15

EQEQ

AUX1

0

PRE

+

6

AUX2

0

PRE

+

6

AUX3

0

PRE

+

6

AUX4

0

PRE

+

6

AUX5

PRE

0

POST

+

6

AUX6

PRE

0

POST

+

6

AUX7

PRE

0

POST

+

6

AUX8

PRE

0

POST

+

6

0

PAN

30

MIC

PK

GAIN

5

60dB

=

LINE

-20

100Hz

-

+

0

33

HF

6

6

9

9

12

12

15

15

3k

13k

550

HI

-

+

0

MID

33

6

6

9

9

12

12

15

15

450

LO

80 1.9k

MID

-

+

0

33

6

6

9

9

12

12

15

15

-

+

0

33

LF

6

6

9

9

12

12

15

15

EQEQ

AUX1

0

PRE

+

6

AUX2

0

PRE

+

6

AUX3

0

PRE

+

6

AUX4

0

PRE

+

6

AUX5

PRE

0

POST

+

6

AUX6

PRE

0

POST

+

6

AUX7

PRE

0

POST

+

6

AUX8

PRE

0

POST

+

6

0

PAN

30

MIC

PK

GAIN

5

60dB

=

LINE

-20

100Hz

-

+

0

33

HF

6

6

9

9

12

12

15

15

3k

13k

550

HI

-

+

0

MID

33

6

6

9

9

12

12

15

15

450

LO

80 1.9k

MID

-

+

0

33

6

6

9

9

12

12

15

15

-

+

0

33

LF

6

6

9

9

12

12

15

15

EQEQ

AUX1

0

PRE

+

6

AUX2

0

PRE

+

6

AUX3

0

PRE

+

6

AUX4

0

PRE

+

6

AUX5

PRE

0

POST

+

6

AUX6

PRE

0

POST

+

6

AUX7

PRE

0

POST

+

6

AUX8

PRE

0

POST

+

6

0

PAN

30

MIC

PK

GAIN

5

60dB

=

LINE

-20

100Hz

-

+

0

33

HF

6

6

9

9

12

12

15

15

3k

13k

550

HI

-

+

0

MID

33

6

6

9

9

12

12

15

15

450

LO

80 1.9k

MID

-

+

0

33

6

6

9

9

12

12

15

15

-

+

0

33

LF

6

6

9

9

12

12

15

15

EQEQ

AUX1

0

PRE

+

6

AUX2

0

PRE

+

6

AUX3

0

PRE

+

6

AUX4

0

PRE

+

6

AUX5

PRE

0

POST

+

6

AUX6

PRE

0

POST

+

6

AUX7

PRE

0

POST

+

6

AUX8

PRE

0

POST

+

6

0

PAN

30

MIC

PK

GAIN

LINE

-20

HF

6

9

12

HI
MID

6

9

12

LO
MID

6

9

12

LF

6

9

12

AUX1

0

PRE

AUX2

0

PRE

AUX3

0

PRE

AUX4

0

PRE

AUX5

PRE

0

POST

AUX6

PRE

0

POST

AUX7

PRE

0

POST

AUX8

PRE

0

POST

PAN

5

=

100Hz

6

9

12

15

550

6

9

12

15

80 1.9k

6

9

12

15

6

9

12

15

EQEQ

PK

60dB

-

+

0

33

6

9

12

15

3k

13k

-

+

0

33

6

9

12

15

450

-

+

0

33

6

9

12

15

-

+

0

33

6

9

12

15

0

+

6

0

+

6

0

+

6

0

+

6

0

+

6

0

+

6

0

+

6

0

+

6

0

L

10

5

0

+16

5

+8

-10

10

15

20

30

L

R

MUTE

10

C

L
R

5

1
2

0

3
4

+16

5

0

+8

-10

10

M
1

15

M
2

20

M
3

M
4

30

PFL

MUTE

0

PFL

L

R

10

C

L
R

5

1
2

0

3
4

+16

5

-10

10

M
1

15

M
2

20

M
3

M
4

30

L

R

MUTE

10

C

L
R

5

1
2

0

3
4

+16

5

+8

0

-10

10

M
1

15

M
2

20

M
3

M
4

30

PFL

L

R

MUTE

10

C

L
R

5

1
2

0

3
4

+16

5

+8

0

+8

-10

10

M
1

15

M
2

20

M
3

M
4

30

PFL

MUTE

0

PFL

L

R

10

C

L
R

5

1
2

0

3
4

+16

5

10

M
1

15

M
2

20

M
3

M
4

30

L

R

MUTE

10

C

L
R

5

1
2

0

3
4

+16

5

+8

0

-10

+8

-10

10

M
1

15

M
2

20

M
3

M
4

30

PFL

L

R

MUTE

C

L
R

1
2

3
4

0

M

1

M

2

M

3

M

4

PFL

R

MUTE

10

5

0

5

10

15

20

30

C

L
R

1
2

3
4

+16

+8

0

-10

M
1

M
2

M
3

M
4

PFL

38 GB4 User Guide

STE1

48V

L

STE

30

MIC
GAIN

STE2

48V

L

STE

PK

MIC
GAIN

PK

30

LINE

-20

HF

HM

LM

LF

AUX1

PRE

AUX2

PRE

AUX3

PRE

AUX4

PRE

AUX5

PRE
POST

AUX6

PRE
POST

AUX7

PRE
POST

AUX8

PRE
POST

BAL

MONO

5

60dB

=

L

R

-

+

0

33

6

9

12

15

15

-

+

0

33

6

9

12

15

15

-

+

0

33

6

9

12

15

15

-

+

0

33

6

9

12

15

15

EQ

+

6

+

6

+

6

+

6

+

6

+

6

+

6

+

6

0

5

60dB

=

LINE

-20

L

MONO

R

-

+

0

33

HF

6

6

9

12

HM

6

9

12

LM

6

9

12

LF

6

9

12

AUX1

0

PRE

AUX2

0

PRE

AUX3

0

PRE

AUX4

0

PRE

AUX5

PRE

0

POST

AUX6

PRE

0

POST

AUX7

PRE

0

POST

AUX8

PRE

0

POST

BAL

6

9

9

12

12

15

15

-

+

0

33

6

6

9

9

12

12

15

15

-

+

0

33

6

6

9

9

12

12

15

15

-

+

0

33

6

6

9

9

12

12

15

15

EQ

0

+

6

0

+

6

0

+

6

0

+

6

0

+

6

0

+

6

0

+

6

0

+

6

0

L

MUTE

10

5

0

+16

5

+8

0

-10

10

15

20

30

PFL

STE1

L

R

C

L
R

1
2

3
4

10

M
1

15

M
2

M
3

M
4

R

MUTE

10

5

0

5

20

30

C

L
R

1
2

3
4

+16

+8

0

-10

M
1

M
2

M
3

M
4

PFL

STE2

39GB4 User Guide

40 GB4 User Guide