TYPICAL SPECIFICATIONS
Frequency Response
Mic/Line Input to any output, 20Hz - 20kHz ...................................... <1dB
THD + N
Mic sens. -30dBu, +20dBu at all outputs @1kHz .......................... <0.006%
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 & Centre Outputs ................................................................ <-83dBu
Aux Outputs (GB2 Groups only) ..................................................... <-80dBu
Matrix Outputs............................................................................... <-89dBu
Crosstalk
(@1kHz, typical)
Input Channel Mute......................................................................... <-97dB
Input Fader cut-off........................................................................... <-95dB
Pan isolation ................................................................................... <-75dB
Mix route isolation........................................................................... <-97dB
Group route isolation....................................................................... <-97dB
Adjacent channel crosstalk.............................................................. <-99dB
Group to Mix.................................................................................... <-84dB
Aux Send pots offness (typical) ....................................................... <-84dB
Matrix Send pots offness (typical) ................................................... <-84dB
GRAHAM BLYTH
Graham Blyth, Soundcraft’s co-founder and Technical
Director, has taken the well established and classic
Soundcraft microphone preamplifier to a new level of
performance, resulting in the new GB30 preamp which
boasts extraordinary clarity with exceptionally controlled
overload characteristics.
Soundcraft’s legendary 4-band EQ has also been
improved further with the addition of elements derived
from Soundcraft’s highly successful MH Series consoles.
This new design delivers the sound of the classic ‘British
EQ’ enhanced even further with more focused HF and LF
shelving sections.
CMRR
Typical @ 1kHz .................................................................................... 80dB
PLEASE NOTE: GB2R noise, crosstalk and CMRR specifications exceed the standard GB Series
specifications, please check the website for full details
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.................................................... 2 x 250mW 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 .................................... 100 - 600Ω
Soundcraft Registered Community Trade Mark/RTM No. 000557827
SOUNDCRAFT
HARMAN INTERNATIONAL INDUSTRIES LTD.,
CRANBORNE HOUSE, CRANBORNE ROAD
POTTERS BAR, HERTS, EN6 3JN, UK
T: +44 (0)1707 665000
F: +44 (0)1707 660742
E: info@soundcraft.com
SOUNDCRAFT USA
8500 BALBOA BLVD.
NORTHRIDGE, CA 91329, USA
T: +1-818-920-3212
F: +1-818-920-3208
E: soundcraft-usa@harman.com
High pass filter (Mono input) .........................................................................100Hz, 18dB per octave
EQ (Mono input)
HF ....................................................... 13kHz, +/-15dB, 2nd order shelving
Hi-Mid......................................................... 550Hz-13kHz, +/-15dB, Q=1.5
Lo-Mid ......................................................... 80Hz-1.9kHz, +/-15dB, Q=1.5
LF.......................................................... 80Hz, +/-15dB, 2nd order shelving
EQ (Stereo input)
HF ....................................................... 13kHz, +/-15dB, 2nd order shelving
Hi-Mid ................................................................... 2.5kHz, +/-15dB, Q=0.8
Lo-Mid ................................................................... 450Hz, +/-15dB, Q=0.8
LF.......................................................... 80Hz, +/-15dB, 2nd order shelving
Metering
Input channels (GB4/GB8) ......... Single tri-colour 4-segment LED bargraph
Outputs (GB4) ................................ 7 tri-colour 12-segment LED bargraphs
Outputs (GB8) ............................. 11 tri-colour 12-segment LED bargraphs,
+ Meterpod with 3 VU meters (L/R/C)
Outputs (GB2/GB2R) ................ 2 tri-coloured 12-segment LED bargraphs,
(indicates monitor source level)
Power consumption
AC mains supply (internal PSU) 85V-270V AC,
50/60Hz universal input
Power consumption ............................................................ Less than 150W
Operating conditions
Temperature range............................................................. -10ºC to +30ºC
Relative humidity........................................................................ 0% to 80%
www.soundcraft.com
Soundcraft reserves the right to improve or otherwise alter any
information supplied in this document or any other documentation
supplied hereafter. E&OE 12/07
This equipment complies with the EMC Directive 89/336/EEC
Part No: ZL0627-04
Note: These figures are typical of performance in a normal electromagnetic environment and are often exceeded. Performance may be
degraded in severe conditions. All measurements refer to electronically balanced inputs and outputs.
PROFESSIONAL
MIXING CONSOLES
THE FULLY PROFESSIONAL LIVE SOUND CONSOLE
YOU THOUGHT YOU COULDN’T AFFORD
Drawing on 30 years of Soundcraft
experience, GB Series consoles set new
standards in professional live sound mixing
on a budget. The GB8 (8-bus) console is
packed with the features you need to create
a memorable FOH and monitor mix,
combining totally re-engineered circuit
topology with our ground-breaking GB30 mic
preamp and EQ designs to deliver a sonic
performance rivalling many high-price, highend consoles.
The GB8 has plenty of bus power for
sophisticated mixing applications. All eight
Aux master controls can be swapped
with eight Groups, and all Auxes
are pre/post switchable globally
per Aux bus from the Master
Section. In addition to the eight
Groups, the GB8 has L/C/R and
eight Aux busses. Four mute
groups provide quick and easy muting
of groups of channels, ideal for scene
changes or where groups of instruments
need to be silenced. And the output matrix is
essential when different zones in a venue
require specifically tailored mixes,
enabling the operator to create
sub-mixes of the Group, L-R
mix and C (mono) busses.
Unlike other mixers in their
class, GB Series consoles
are built to last with a rigid
steel chassis, high quality
vertically mounted PCB channel
strips and individually nutted potentiometers
ensuring reliability in both fixed installations
and on the road.
And because Soundcraft understands
the way that live sound
engineers work, you’ll find
an intuitive control
surface and a
conveniently angled
rear connector
panel, so you can do
all your patching
without ever leaving the
mix position.
GB8 FEATURES:
• 16, 24, 32, 40 and 48 channel frame sizes
• 19 busses
• 4 full feature stereo channels
• 4 stereo returns
• 8 Aux sends (all are pre/post
switchable)
• 8 sub groups (SWAP with all 8 Auxes)
• 11x4 output matrix
• Record output with limiter
• Alternate stereo output with limiter
• 1kHz oscillator
• Meterpod with 3 high definition LED VU
meters (L/C/R)
• Internal jumpers switch pre-fade Aux sends
to pre-EQ
• GB30 mic preamp and precision
equalisation circuitry
• Direct outputs on every channel
• Talkback facility
• 100mm faders
• Switchable 48V phantom powering on every
channel
• 18dB/octave high pass filter
• 4 mute groups
• 12-segment LED metering
DUAL-MODE TOPOLOGY,
STRAIGHT FROM THE SOUNDCRAFT MH SERIES
With dual-mode topology derived from
Soundcraft’s acclaimed MH Series, the GB8
and GB4 consoles provide ideal live sound
mixing solutions for medium-sized venues
including clubs, theatres and houses of
worship. With a single button press on the
GB4 (4-bus), any of the first four Aux master
controls can be swapped with the
respectively numbered Group fader, providing
the flexibility to work at FOH, Monitors, or
perform both duties simultaneously.
The GB4 has L/C/R and eight Aux busses in
addition to its four groups and, like the GB8,
there are four mute groups and an output
matrix for creating zoned mixes.
Like all GB series mixers, the GB4 uses
GB30 mic preamps which use local
linearisation techniques rather than global
feedback to deliver an extremely open
frequency response and excellent phase
linearity. The GB30 EQ borrows the innovative
designs developed for the Soundcraft MH4
console, providing GB users with the benefits
of genuine high-end equalisation. And thanks
to a meticulous ‘ground-up’ approach to
circuit and mechanical design, the GB Series
exhibits class-leading noise performance and
channel isolation figures.
When it comes to recording a performance,
the GB4 & GB8 are similarly well equipped
with pre-/post-fader switchable direct
outputs on every channel and a high-quality
limiter on dedicated record outputs fed from
the L-R mix bus.
GB4 FEATURES:
• 12, 16, 24, 32 and 40 channel frame sizes
• 15 busses
• 2 full feature stereo channels
• 2 stereo returns
• 8 Aux sends (4 are pre/post switchable)
• 4 sub groups (SWAP with Auxes 1-4)
• 7x4 output matrix
• Record output with limiter
• GB30 mic preamp and precision equalisation
circuitry
• Direct outputs on every channel
• Talkback facility
• 100mm faders
• Switchable 48V phantom powering on every
channel
• 18dB/octave high pass filter
• 4 mute groups
• 12-segment LED metering
Dedicated record outputs with a high-quality
limiter are fed from the L-R mix bus.
SMALLER SCALE MIXING,
WITHOUT THE COMPROMISES
Available in 16, 24 and 32 channel
configurations, the GB2 is designed for
installed sound and A/V applications that
don’t require all the sophisticated
functionality of the GB4 and GB8. However
the GB2 is a genuine GB Series console in
every respect, with sound quality assured by
GB30 Mic Pre and Equaliser designs, and
reliability by the same rugged build quality
that has made the GB4 and GB8 so
dependable in demanding professional
applications.
Along with six Aux busses and an integral
6 x 2 matrix, four subgroups are provided as
two stereo pairs, with a unique facility for
adjusting the width of the stereo signal
across the stereo mix. The channel pan
settings are retained on the group outputs,
while the degree of stereo separation to the
mix bus is independently adjustable from full
stereo through to mono.
The GB2 also features two stereo input
channels, with separate mic and line inputs.
In normal use, the mic inputs are routed to
the local channel and the line inputs act as
a stereo return to the mix bus. Selecting the
line input to the local channel overrides the
mic inputs.
GB2 FEATURES:
• 16, 24, 32 channel frame sizes
• 12 busses
• 2 full feature stereo channels
• 2 stereo returns (on stereo channels)
• 6 Aux sends
• 4 sub groups (paired)
• 6x2 output matrix
• GB30 mic preamp and precision equalisation
circuitry
• Direct outputs on every mono channel
• Talkback facility
• 100mm faders
• Switchable 48V phantom powering on every
channel
• 100Hz high pass filter
• 12-segment LED metering
• Record output
Line inputs on the stereo channels can also
act as a stereo return.
GB MIXING POWER IN A COMPACT
RACK-MOUNTING FORMAT
With a convenient, rack-mountable format,
the GB2R packs GB Series features and
sound quality into a compact mixer, ideal for
use in fixed installations or a touring rack.
Available in 12 mono/2 stereo channel
(GB2R 12/2) or 16 mono channel (GB2R
16) versions, the versatility of the GB2R is
enhanced by a rotatable connector pod for
top or rear cable entry, enabling use in a
variety of mounting configurations.
Both models feature the same GB30 Mic Pre
and Equaliser designs found in all GB
mixers, ensuring exceptional sound quality.
In addition, there are six Aux busses,
switchable phantom power on every mic
input and direct outputs for every channel.
Precision output level control is facilitated by
dual faders on the master stereo output,
and for capturing live performances phono
connectors provide a high-quality direct
recording solution.
Patching in outboard processors is made
simple by two Stereo Returns with level
controls to Mix or Sub Group Outputs (12/2
version only) and to Aux 1 & 2.
In addition to a stereo sub group, the GB2R
12/2 adds two fully-featured stereo input
channels, each with two Mic inputs and
separate Line inputs, switchable direct to Mix
as another effects return, or into the local
channel (overriding the Mic input).
GB2R FEATURES:
• 19" rack-mountable or tabletop mixer
• 12/2 channel version with 12 mono inputs
and 2 stereo inputs, stereo Sub Group
Output, Mix and Mono Sum Outputs – total
inputs to mix 26
• 16 channel version with 16 mono inputs,
Stereo Mix and Mono Sum outputs – total
inputs to mix 22
• 8 (GB2R 16) or 10 (GB2R 12/2) busses
• 2 stereo inputs (GB2R 12/2 only)
• GB30 mic preamp and precision equalisation
circuitry
• 6 Aux Outputs
• Direct Outputs on every mono channel
• 100mm faders
• Switchable +48V phantom power on every
mic input
• 100Hz high pass filter
• 12-segment LED metering
• Internal switched mode power supply
• Record output
Rear connector panel can be rotated to
facilitate use on a desktop or in a rack.
GB8 & GB4 INPUTS
MONO INPUT MODULE
Mic Input
A balanced XLR connector accepts balanced or unbalanced mic
signals.
GB2 & GB2R INPUTS
Level Control and Routing
On the GB4, the signal on each fader can be routed to the L-R mix (via
the Pan control), the C (mono) bus and Groups 1&2 and 3&4. On the
GB8, the signal can additionally be routed to Groups 5&6 and 7&8
(Fig. 2).
Line Input
A balanced 1/4" jack accepts balanced or unbalanced line level
sources, such as keyboards.
EQ Section
Mic Input
A balanced XLR connector accepts balanced or unbalanced mic
signals.
Line Input
Pan
Turning the pan control full left or right enables odd or even groups or
the left or right Mix bus to be accessed individually.
+48V Phantom Power
Phantom power is individually switchable on every channel, with front
panel LED indication of status.
MONO INPUT MODULE
A balanced 1/4" jack accepts balanced or unbalanced line level
sources, such as keyboards.
+48V Phantom Power
Solo/PFL
Each channel can be soloed pre-fader, post-EQ to check levels. PFL
status is indicated via a front panel LED.
Phase Reverse
Phantom power is individually switchable on every channel, with front
panel LED indication of status.
Phase Reverse
Phase reverse is individually switchable on every channel.
100mm Fader
Phase reverse is individually switchable on every channel.
EQ Switch
Input Stage
Professional grade, 100mm faders provide accurate, consistent control
of audio levels and have superb cut-off performance.
Input Stage
The EQ section can be bypassed using the EQ switch, allowing comparison
of treated and untreated sounds without having to reset controls.
Metering
Precision, low noise mic preamps deliver continuously variable gain
between 5B and 60dB. A Peak LED indicates internal signal levels in
excess of +18dBu.
Precision, low noise mic preamps deliver continuously variable gain
between 5dB and 60dB. A Peak LED indicates internal signal levels in
excess of +18dBu.
A 4-segment LED display on each GB4/8 fader strip provides an
instant reference for the signal level on that channel.
High Pass Filter
A steep 18dB per Octave High Pass Filter is included straight after the
preamp to reduce low frequency rumble on stage and clean up vocal
performances.
Insert
A pre-fade, pre-EQ (but post-HPF) insert point is provided for patching
in Limiters, Graphic Equalisers or other signal processors. It may also
be used for recording.
Direct Output
A direct output is also available on every mono channel with individual
pre/post fader switching situated on the rear panel. This allows the
direct outputs to be equally useful for effects send applications or
multitrack tape feeds.
EQ Section
GB Series consoles incorporate the GB30 4-band equaliser section based on that used in the high-end MH Series. Both the HF and LF
shelving sections have steeper slopes than usual which substantially
reduces mid frequency harshness in the HF band and muddiness in the
LF. This increase in “cleanliness” of response is further enhanced by an
element of undershoot and overshoot in the boost/cut response. It has
two swept mid frequencies carefully selected for optimum control
during live performances. All bands provide 15dB of cut or boost. The
Low frequency equaliser response shelves at 80Hz. The swept Lo Mid
control operates between 80Hz and 1.9kHz. The swept Hi Mid control
operates at frequencies between 550Hz and 13kHz. The fixed High
frequency equaliser response shelves at 13kHz.
High Pass Filter
STEREO INPUT MODULE
The stereo inputs (2 on the GB4, 4 on the GB8) allow connection of
stereo sources, or use as sophisticated effects returns. GB8 has four
stereo inputs. The stereo input channels share all features with the
mono input channels, with the exception of the following:
Connections
Each channel is equipped with both balanced jack and XLR pairs. The
left or right input can be selected, if required, as a single, mono source
to be routed to both paths. Alternatively both the left and right signals
can be mono-summed.
EQ Section
The equaliser section provides 15dB of cut or boost at each of 4bands: a HF shelf at 13kHz; Hi-Mid at 2.5kHz; Lo-Mid at 450Hz; and a
LF shelf at 80Hz.
A steep 18dB per Octave High Pass Filter is included straight after the
preamp to reduce low frequency rumble on stage and clean up vocal
performances.
Insert
A pre-fade, pre-EQ (but post-HPF) insert point is provided for patching
in Limiters, Graphic Equalisers or other signal processors. It may also
be used for recording.
Direct Output
A direct output is also available on every mono channel with individual
pre/post fader switching situated on the rear panel. This allows the
direct outputs to be equally useful for effects send applications or
multitrack tape feeds.
The 6 Auxiliary sends are pre fade (1 & 2), pre/post selectable (3 & 4)
and post fade (5 & 6).
Level Control and Routing
On the GB2R the signal can be routed to the Stereo Mix and the Sub
Group (12/2 model only). For GB2, the signal can be routed to the
Stereo Mix, and Groups 1&2 and 3&4.
Pan
Turning the pan control full left or right enables odd or even groups or
the left or right Mix bus to be accessed individually.
Solo/PFL
Each channel can be soloed pre-fader, post-EQ to check levels. PFL
status is indicated via a front panel LED.
100mm Fader
Metering
Both GB2 and GB2R input channels feature peak and signal leds.
STEREO INPUT MODULE - GB2 and GB2R 12/2 only
The 2 stereo inputs allow connection of stereo sources, or use as
sophisticated effects returns. The stereo input channels share all
features with the mono input channels, with the exception of the
following:
Connections
The EQ section can be bypassed using the EQ switch, allowing comparison
of treated and untreated sounds without having to reset controls.
Each channel is equipped with both balanced jack and XLR pairs. The
left or right input can be selected, if required, as a single, mono source
to be routed to both paths. Alternatively both the left and right signals
can be mono-summed.
Auxiliary Sends
EQ Section
The GB4 has 8 flexible Auxiliary sends which allow the choice of either
monitor or effects orientated mixes. Auxes 1-4 are pre-fader and, in
normal operation, are routed to the rotary Aux masters 1-4. In SWAP
mode, they are routed to Group faders 1-4 and Group meters 1-4, ideal
for monitor mixing applications. Auxes 5 to 8 are pre/post switchable globally assigned selectable per Aux bus from the Master Section.
The equaliser section provides 15dB of cut or boost at each of
4-bands: a HF shelf at 13kHz; Hi-Mid at 2.5kHz; Lo-Mid at 450Hz; and
a LF shelf at 80Hz.
Stereo Return
When the XLR/Mic input is selected to the channel, the Line input can
be switched to mix as an effects return or as another input to mix.
When the Line input is switched to the channel, the XLR/Mic input is
disconnected.
The GB8’s 8 Auxiliary sends (Fig. 1) are globally selectable per Aux bus
between pre/post fade. The Auxes are routed to rotary Aux masters,
which all feature SWAP mode.
GB4 Stereo
Input Channel
Auxiliary Sends
Professional grade, 100mm faders provide accurate, consistent control
of audio levels and have superb cut-off performance.
EQ Switch
GB4 Mono
Input Channel
GB Series consoles incorporate the GB30 4-band equaliser section based on that used in the high-end MH Series. Both the HF and LF
shelving sections have steeper slopes than usual which substantially
reduces mid frequency harshness in the HF band and muddiness in the
LF. This increase in “cleanliness” of response is further enhanced by an
element of undershoot and overshoot in the boost/cut response. It has
two swept mid frequencies carefully selected for optimum control
during live performances. All bands provide 15dB of cut or boost. The
Low frequency equaliser response shelves at 80Hz. The swept Lo Mid
control operates between 80Hz and 1.9kHz. The swept Hi Mid control
operates at frequencies between 550Hz and 13kHz. The fixed High
frequency equaliser response shelves at 13kHz.
Fig.1 GB4/8 Channel
strip detail, Auxiliary
Controls.
Fig.2 GB4/8 Channel
strip detail, Fader
section.
Fig.1 GB2R 12/2 Mono
channel fader
panel.
Fig.2 GB2R 16 Mono
channel fader
panel.
Fig.3 GB2R 12/2 Stereo
channel input
section.
Fig.4 GB2R 12/2 Stereo
channel fader
panel.
GB2
Mono Input
Channel
GB2
Stereo Input
Channel
GB4 OUTPUTS & MASTER
GB8 OUTPUTS & MASTER
GROUP SECTION
Group Outputs
Each Group has an impedance-balanced XLR output
connector, allowing long cable runs on stage.
Insert Points
Pre-fade insert points are provided on jack
connectors, for the connection of Limiters, Graphic
Equalisers or other signal processors.
Group Metering
GB4 has four 12-segment peak reading bargraph
meters which display Group (or Aux 1-4 in SWAP
mode) output levels.
Rec/Alt Output
GB4 has a single Rec/Alt section. Outputs are
provided on impedance balanced 1/4" jacks and
unbalanced -10dBv phono connectors. They
provide a post-fade send from the L-R mix. The C
(mono) bus may be added and/or the mix can be
mono summed. A rotary control governs level and
a switchable limiter is provided.
Four rotary controls per Group allow individual
assignment to Matrices 1-4.
Matrix Masters
The level at each Matrix output (balanced jack) on
the rear panel is controlled by a rotary control, with
a button for AFL.
Auxiliary Masters
The level at each Auxiliary output (balanced jack)
on the rear panel is controlled by a rotary control
with a button for AFL.
Group/Aux SWAP
GB4 has four push buttons which swap the
functions of Auxiliary 1-4 master rotary controls
and Group master faders. NB: The 12-segment
peak reading bargraph meters always display the
signal selected to the Group faders, i.e. Groups in
normal operation, or Auxes when used in SWAP
mode.
Routing
The signal on each Group fader can be routed to
either the L-R mix (via the Pan control) or to the C
(mono) bus.
100mm Group Faders
The Group faders provide 10dB of extra gain above
the zero mark, whilst still ensuring smooth
operation. Each Group is also equipped with AFL.
GB4 Outputs & Master
GB8 has 8 12-segment peak reading bargraph meters which display
Group (or Aux 1-8 in SWAP mode) output levels.
Group/Aux SWAP
GB8 has eight push buttons which swap the functions of Auxiliary 1-8
master rotary controls and Group master faders. NB: The 12-segment
peak reading bargraph meters always display the signal selected to the
Group faders, i.e. Groups in normal operation, or Auxes when used in
SWAP mode.
GB4 has two stereo returns - provided for use with
effects units, or as simple stereo instrument
inputs. The rotary controls govern level. Ste Ret 1
and 2 can be routed to Groups 1/2 and 3/4
respectively, or the main L-R mix.
CONTROL ROOM SECTION
The control room section allows the engineer to
monitor either the 2-track return, the C (Mono)
Bus, or the Mix via the control room outputs or
headphones. A headphone jack is provided for use
with headphones with impedances of 100 Ohms
or greater. Both the control room and 2-track
return levels can be altered using the associated
controls. It is also possible to replace the Mix
output signal with the 2-track return by pressing “2
TRK TO MIX”. This allows easy playing of pre-show
music at a single button press, without having to
make any alterations to the band’s settings.
MASTER SECTION
Rec/Alt Output
GB8 features separate Record and Alternate output sections. Outputs
are provided on impedance balanced 1/4" jacks and unbalanced
-10dBv phono connectors. They provide a post-fade send from the L-R
mix. The C (mono) bus may be added and/or the mix can be mono
summed. A rotary control governs level and a switchable limiter is
provided.
Talkback Section
GB8 additionally features a 1kHz oscillator with identical routing to the
talkback.
Stereo Returns
GB8 has four stereo returns - provided for use with effects units, or
as simple stereo instrument inputs. The rotary controls govern level.
Ste Ret 1, 2, 3 and 4 can be routed to Groups 1/2, 3/4, 5/6 and
7/8 respectively, or the main L-R mix.
Metering
TRUE VU METERS
Three 12-segment Peak reading bargraph meters
display L-R mix and C (mono) bus output levels
when the appropriate control room selection is
made. If any input or Auxiliary master is soloed
then the PFL/AFL LED illuminates, and the master
meters show PFL/AFL levels instead.
GB8 boasts 3 true VU ballistic (ANSI C16.5) LED meters, which display
the left, right and C (Mono) outputs. The correct classic VU response is
achieved by using 2nd order rectifier filters, not something you see
every day!
Matrix Assignment
MASTER SECTION
Connections
100mm Master Faders
L-R mix and C (mono) bus outputs appear on
balanced XLR with jack insert points. The L-R mix is
also provided on two pairs of balanced jack
outputs and one pair of RCA/phono outputs. A
balanced XLR input allows a talkback mic to be
connected. Two control room outputs for engineer
monitoring are available on impedance balanced
1/4" jacks.
Mix and C (Mono) Output levels are controlled by
custom-built 100mm long throw faders. The Mix
outputs may be routed to the C (Mono) bus should
only a mono PA be required, or an induction loop
need to be fed.
A pair of unbalanced -10dBv phono connectors
labelled “2TRK In” allow pre-show music to be
replayed. An independent 2 TRK rotary level control
is also provided.
Group Metering
Once connected, the engineer’s talkback mic can
be routed to all Groups and/or Aux 1-2, 3-4, 5-6 &
7-8. A rotary control governs talkback level.
Any of the four Group masters, Left, Right and C
(mono) buses can be routed to any of the four
matrix outputs via individual rotary controls.
2TRK Inputs
GROUP SECTION
Talkback Section
Stereo Returns
Matrix Assignment
THE GB8 OUTPUTS & MASTER SECTION HAVE THE SAME
FEATURES AS THE GB4, PLUS THE FOLLOWING
PERFORMANCE ENHANCEMENTS.
PSU Indicators
A red LED illuminates if the console is powered up,
showing the status of the +/-17v voltage rails.
Integral Power Supply
The console is fitted with a high-efficiency SMPS
design (Switched Mode Power Supply) unit that
makes for cooler operation and lighter weight. The
PSU is capable of accepting a wide range of AC
input voltages without any internal or external
switch changes. An external DPS-3 power supply
may be connected for redundancy operation.
GB8 Outputs & Master
GB2 OUTPUTS & MASTER
GROUP SECTION
Group Outputs
Each Group has an impedance-balanced XLR output
connector, allowing long cable runs on stage.
Rec Output
Recording outputs are provided on -10dBv phono
connectors. They provide a post-fade send from the
L-R mix.
GROUP SECTION - GB2R 12/2 Only
CONTROL ROOM SECTION
Sub Group Output
The control room section allows the engineer to
monitor either the 2-track return, Mix or Sub
Groups (12/2 model only) via the control room
outputs or headphones. A headphone jack is
provided for use with headphones with
impedances of 100 Ohms or greater. Both the
control room and 2-track return levels can be
altered using the associated controls. It is also
possible to switch the 2-track return input to Mix,
adding to whatever signal is already present on the
mix output, by pressing “2 TRK TO MIX”. This allows
easy playing of pre-show music at a single button
press, without having to make any alterations to
the band’s settings.
The Sub Group has an impedance-balanced XLR
output connector, allowing long cable runs on stage.
Insert Points
Talkback Section
Insert Points
Pre-fade insert points are provided on jack
connectors, for the connection of Limiters, Graphic
Equalisers or other signal processors.
Once connected, the engineer’s talkback mic can
be routed to all Groups and/or Auxes. A rotary
control governs talkback level.
Pre-fade insert points are provided on jack
connectors, for the connection of Limiters, Graphic
Equalisers or other signal processors.
Group Metering
Stereo Returns
Group Metering
Selectable 12-segment peak reading bargraph
meters.
Stereo returns are accommodated via the stereo
inputs. These can be switched for simultaneous
mic/stereo return use, or for line inputs (see
inputs).
Selectable 12-segment peak reading bargraph
meters.
Matrix Assignment
One rotary control per Group allows individual
assignment to Matrices 1-2.
Matrix Masters
The level at each Matrix output (XLR) on the rear
panel is controlled by a rotary control, with buttons
for AFL and Mute.
Auxiliary Masters
The level at each Auxiliary output (XLRs 1-4,
balanced jacks 5-6) on the rear panel is controlled
by a rotary control with a button for AFL.
Routing
The signal on each Group fader can be routed to
the L-R mix.
Stereo Width
The channel pan settings are retained on the group
outputs, while the degree of stereo separation to
the mix bus is independently adjustable on rotary
controls from full stereo through to mono.
100mm Group Faders
The Group faders provide 10dB of extra gain above
the zero mark, whilst still ensuring smooth
operation.
MASTER SECTION
Connections
L-R Mix and a mono sum output appear on
balanced XLR with jack insert points on the L-R
outputs. A balanced XLR input allows a talkback
mic to be connected. Two control room outputs for
engineer monitoring are available on impedance
balanced 1/4" jacks. L and R signals may be fed
to each of the 2 matrix busses.
2TRK Inputs
A pair of unbalanced -10dBv phono connectors
labelled “2TRK In” allow pre-show music to be
replayed. An independent 2 TRK rotary level control
is also provided.
GB2 Outputs & Master
GB2R OUTPUTS & MASTER
CONTROL ROOM SECTION
The control room section allows the engineer to
monitor either the 2-track return, Groups 1&2 and
3&4, or the Mix via the control room outputs or
headphones. A headphone jack is provided for use
with headphones with impedances of 100 Ohms
or greater. Both the control room and 2-track
return levels can be altered using the associated
controls. It is also possible to switch the 2-track
return input to Mix, adding to whatever signal is
already present on the mix output, by pressing
“2 TRK TO MIX”. This allows easy playing of
pre-show music at a single button press,
without having to make any alterations to the
band’ssettings.
Metering
12-segment Peak reading bargraph meters can be
selected to display 2-track return, Groups 1&2 and
3&4, or the Mix when the appropriate control
room selection is made. If any input or Auxiliary
master is soloed then the PFL/AFL LED illuminates,
and the master meters show PFL/AFL levels instead.
Auxiliary Masters
The level at each Auxiliary output (XLRs 1-4,
balanced jacks 5-6) on the rear panel is controlled
by a rotary control with a button for AFL.
Routing
The signal on the sub group fader can be routed to
the L-R mix, and/or mono-summed.
100mm Group Faders
The Group faders provide 10dB of extra gain above
the zero mark, whilst still ensuring smooth
operation.
MASTER SECTION
Connections
L-R Mix and a mono sum output appear on
balanced XLR with jack insert points on the L-R
outputs. Two control room outputs for engineer
monitoring are available on impedance balanced
1/4" jacks.
2TRK Inputs
Metering
12-segment Peak reading bargraph meters can be
selected to display 2-track return, Mix or Sub
Group (12/2 model only) when the appropriate
control room selection is made. If any input or
Auxiliary master is soloed then the PFL/AFL LED
illuminates, and the master meters show PFL/AFL
levels instead.
100mm Master Faders
Output levels are controlled by dual 100mm long
throw mix faders.
Integral Power Supply
The console is fitted with a high-efficiency SMPS
design (Switched Mode Power Supply) unit that
makes for cooler operation and lighter weight. The
PSU is capable of accepting a wide range of AC
input voltages without any internal or external
switch changes.
A pair of unbalanced -10dBv phono connectors
labelled “2TRK In” allow pre-show music to be
replayed. An independent 2 TRK rotary level control
is also provided.
100mm Master Faders
Output levels are controlled by a 100mm long
throw mix fader. The Mix outputs may be routed to
the C (Mono) bus should only a mono PA be
required, or an induction loop need to be fed.
Integral Power Supply
The console is fitted with a high-efficiency SMPS
design (Switched Mode Power Supply) unit that
makes for cooler operation and lighter weight. The
PSU is capable of accepting a wide range of AC
input voltages without any internal or external
switch changes. An external DPS-3 power supply
may be connected for redundancy operation.
Auxiliary Masters
The level at each Auxiliary output (XLRs 1-4,
balanced jacks 5-6) on the rear panel is controlled
by a rotary control with a button for AFL.
Rec Output
Recording outputs are provided on -10dBv phono
connectors. They provide a post-fade send from the
L-R mix.
Stereo Returns
Two stereo returns are available with Level controls
to Mix, Aux 1 and Aux 2, and on the 12/2 model to
sub group.
GB2R 12/2 Outputs & Master
GB2R 16 Outputs & Master
GB4 SYSTEM BLOCK DIAGRAM
GB8 SYSTEM BLOCK DIAGRAM
GB2/GB2R SYSTEM BLOCK DIAGRAMS
AUX PRE MODE
POST/PRE EQ
MIC
MUTE
+6
AUX1
DEFAULT
EQ
SUB L-R (GB2R 12-2)
GAIN
5-60dB
SOLO EN
PFL/AFL
MIX L - R
GRP 1 - 4(GB2)
AUX 1 - 6
+48
TOP PANEL, CONNECTORS, DIMS & WEIGHTS
+6
AUX2
+10dB
3-4
PRE
MIC+
100Hz
MICLINE
LF
LINE+
+6
AUX3
FADER
L MID
H MID
-20dB
LINEINS
+6
AUX5
INS SEND
NB: GB2R 16 shown.
PEAK
INS RETN
DEFAULT
PFL
+6
AUX6
AUX 5 - 6 MODE:
POST OR FOLLOW
AUX 3 - 4
PRE
DIRECT
GB2R
OVERHEAD VIEW
NB: GB8 32 channel
model shown. GB4 and
GB2 Channel and
Outputs & Master section
differences are
highlighted in the
preceding pages.
+6
AUX4
SIGNAL
PRESENT
HF
GB8/GB4/GB2
OVERHEAD VIEW
GB2 1-2
GB2R12-2 SUB
PAN
(ON REAR CON)
R
IDENTICAL FOR
GROUPS 3 - 4(GB2)
L
MONO INPUT
MIX
REAR PANEL CONNECTIONS
REAR PANEL CONNECTIONS
NB: GB8 32 channel
model shown.
NB: GB2R 12/2
shown.
STEREO INPUT (NOT GB2R 16)
+48
+6
AUX1
MIC GAIN
5-60dB
EQ
MUTE
FADER
BAL
+10dB
LINE TO MIX/
LINE TO CHAN
+6
AUX2
3-4
PRE
LF
LINE
L MID
H MID
+6
AUX3
HF
+6
AUX4
SIGNAL
PRESENT
-7
LINE+
LINE-
DIMENSIONS & WEIGHTS
PFL
+6
AUX5
PEAK
L
MONO
R
DEFAULT
+6
AUX6
AUX 5 - 6 MODE:
POST OR FOLLOW
AUX 3 - 4
MIC R
+10dB
IDENTICAL FOR
GROUPS 3 - 4(GB2)
+17
MIC-
GB8
GB2 1-2
GB2R12-2 SUB
MIC+
-17
LINE R
LF
L MID
H MID
MIX
HF
-7
LINE+
LINE-
MIX OUT L - R
SUB OUT L-R GRP OUT 1-4
+16dB
AUX 1
AUX 3
+16dB
INV
AUX 5
INV
+16dB
INV
AUX 1
OUT
AUX 5
OUT
AUX 3
OUT
AFL
AFL
AFL
SWITCH FITTED
ON GB2R 12-2 MIX
LINKS FITTED
ON GB2R 16
LEVEL
STE RET 1 L
Weight
16 Ch
24 Ch
32 Ch
40 Ch
48 Ch
25kg (55.1lbs)
30kg (66.1lbs)
35kg (77.2lbs)
40kg (88.2lbs)
45kg (99.2lbs)
984mm (38.74")
1208mm (47.56")
1442mm (56.77")
1666mm (65.59")
1889mm (74.37")
GB4
Frame Size Width
Weight
12 Ch
16 Ch
24 Ch
32 Ch
40 Ch
20kg (44.1lbs)
22kg (48.5lbs)
27kg (59.5lbs)
32kg (70.5lbs)
37kg (81.6lbs)
730mm (28.73")
842mm (33.13")
1065mm (41.93")
1300mm (51.17")
1523mm (59.96")
SUB
TO AUX 1 FOR STEREO RET 1
TO AUX 2 FOR STEREO RET 2
GB2
AUX 1
PRE
STE RET 1 R
SUBL
+10dB
INV
STEREO RTN 2
AS ABOVE
SUBL
INSERT
MIX
SUB L
OUT
MONO
SUBR +10dB
GRP1
+6
GRP2
+6
GRP3
+6
GRP4
+6
MIXL
+6
MIXR
+6
Frame Size Width
Weight
16 Ch
24 Ch
32 Ch
22kg (48.5lbs)
25kg (55.1lbs)
30kg (66.1lbs)
790mm (31.10")
1013mm (39.88")
1247mm (49.09")
656mm (25.83")
*NB The Meterpod is only available on the GB8
AFL
INV
+16dB
SUBR
INSERT
SUB R
OUT
GRP1
MATRIX
MUTE
INV
+10dB
Rear connector panel rotated
for rack mounting
GB2R
INV
GRP1
OUT
MATRIX 2 AS ABOVE
WIDTH
TB GAIN
+10dB
AUX 1-4
GRPS
TB MIC
INV
GRP2
INSERT
+18dB
GRP2
OUT
2 TK L
GB2R 16
2TK
LEVEL
GROUPS 3, 4
AS ABOVE
+18dB
2 TK R
REC R
300mV
+6dB
MNTR R
C/RM
LVL
L
440mm (17.32)
without rack ears
R
+18
+18
+10dB
2TRK
+20dB
-20
MIX L
INSERT
H/PHONES
+20dB
+10dB
MIX R
OUT
PHNS
LVL
PEAK
READING
RECTIFIER
1-2
445m
m (17
-20
PEAK
READING
RECTIFIER
3-4
MONO
OUT
MNO
MIX R
INSERT
PFL/AFL
SOLO ENABLE
INV
.52")
12.5kg (27lbs)
")
MIX L
OUT
INV
483mm (19")
with rack ears
+6dB
MNTR L
MIX
FDR
440mm (17.32")
without rack ears
REC L
300mV
MIX
PFL
INV
Weight
12.5kg (27lbs)
(3.15
GRP2
GB2R 12/2 483mm (19")
with rack ears
80mm
PFL
Width
MATRIX 1
OUT
8")
MIX
m (7.4
GRP1
INSERT
190m
SOLO EN
PFL/AFL
MIX L - R
SUB L-R GRP 1 - 4
AUX 1 - 6
AUX 2, 4, 6 AS BELOW
Frame Size Width
10mm (0.39")
+17
-17
MICLINE L
159mm (6.26")
MIC+
235mm (9.23")*
MIC L
MIX
57mm
SUB
(2.24"
)