Soundcraft GB4 Professional Mixing Console
Soundcraft is a Professional audio company known for its high quality, reasonable cost products. Working hard to develop new products, their most recent development is the GB4 Audio Mixing Console. Mounted in a rigid steel chassis, it is built to last. Moreover, because of its a modular design where each channel is individual, the GB4 is a reliable unit for both fixed installations and use on the road. To further diversify this console, it comes with the option of 12, 16, 24, 32, and 40 channels making it suitable for small, medium, and large churches. The GB4 is better than its predecessors due to its newly designed features to help better meet your needs. It is capable of creating specifically tailored sub-mixes and delivering them to various speakers and locations. The main L-R channel has four outputs which may also be sent to remote locations or recorders. The mic preamps have been improved to deliver an extremely open frequency response and phase linearity. Also, each channel offers tailored equalization frequencies and there is more flexibility and control with the group selection, routing, and auxiliaries. To make live mixing even easier and smoother, the GB4 has four mute groups which you can specially tailor to your sound needs. Simply program the groups of channels you may want muted occasionally (such as instruments, vocals, or a combination) to provide quick and easy group muting while running the live sound. As more and more churches are starting to record their own services, mixing consoles need to meet this need. The GB4 is well equipped for this task as it has pre/post-fader switchable direct outputs on every channel and a high quality limiter on the record outputs fed from the L-R channel mix.
Key Features for Soundcrafts GB4:
- Performance improvements with the new GB30 mic. pre-amp - 4-band precision equalization circuitry - comes in a 12, 16, 32, and 40 channel frame size - 8 Auxiliary sends (4 of which are pre/post switchable) - Talkback facility - Individually switched 48V phantom power on every mono input channel - 4 sub groups (paired) - 4 mute groups - 12-segment LED audio indicator - Record output with limiter - Easy service construction - 7+4 Output Matrix - Integral power supply, with an external power supply link option - All metal TRS jacks and Neutrik XLRs - Direct outputs on all mono input channels

Stereo

Mono Input Module:
(mono picture located on Left side of page) Mic. input: balanced XLR connector which accepts balanced or unbalanced mic signals Line input: balanced 1/4" jack accepts balanced or unbalanced line level sources (ie: keyboard, guitar.) +48 Phantom power: individually switchable on each channel Phase reverse: individually switchable on every channel Input stage: precision, low noise mic preamps deliver continuously variable gain between 5dB and 60dB High pass filter: Provides 18dB/Octave attenuation below 100Hz Insert: The insert point on every channel is pre-EQ, pre-fader. Direct output: pre/post-fader switchable direct output is available on every mono channel EQ section: On/Off switchable 4-band equalizer section to provide HF/LF roll off and frequency sweep through Lo-Mid and Hi-Mid frequencies Auxiliary sends: 8 Auxiliary sends which have flexible pre/post switching; Auxes 1-4 are pre-fader and, under normal operation, are routed to the rotary Aux masters 1-4. In SWAP mode, they are routed to Group faders 1-4 and Group metres1-4, ideal for monitor mixing applications Routing: The signal on each fader can be routed to the L-R mix (via the Pan control), the C(mono) bus, and Group(s) 1&2 and 3&4 Pan: Enables odd/even Groups or L-R mix bus to be accessed individually Solo/PFL: Each channel can be soloed pre-fader, post-EQ to check levels 100mm fader: Provides accurate, consistant control of audio levels Mastering: A 4-segment LED display on each fader strip provides an instant reference for the signal level on that channel.

Stereo Input Module:

(stereo channel picture located on right) There are two stereo inputs to allow the connection of stereo sources or to use as a sophisticated effects returns. Connection: Each channel is equipped with both balanced jacks 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 4-band equalizer section provides HF/LF roll off and fixed-frequency Lo-Mid and Hi-Mid boost/attenuation.

Group Section:

Group outputs: A balanced XLR output is provided for each Group Insert points: Pre-fade insert points are provided on jack connectors Group Metering: Four 12-segment peak reading bar graph metres display Group (or Aux 1-4 in SWAP mode) output levels Output Matrix: The output matrix routes the Groups and Main L, R, and C (mono) signals to four matrix (balanced jack) outputs which can feed to remote locations Matrix assignment: Four rotary dials are assigned to each Group to allow Group signal to be sent to the four output Matrices Matrix masters: The level of each Matrix output (balanced jack) on the rear panel is controlled by a rotary dial; each Matrix also has a button for AFL. Auxiliary masters: Each of the eight Auxiliary (balanced jack) outputs located on the rear panel is assigned to eight corresponding rotary dials to control the level; each Auxiliary also has a button for AFL Group/Aux SWAP: A push button is assigned to each of the first four Auxiliaries allowing the Aux 1-4 master rotary dials and the Group faders to be interchanged. Note: The 12-segment peak reading bar graph metres display the signal assigned to each Group fader (ie: display Groups 1-4 under normal condition; display Auxes 1-4 in SWAP mode) Routing: The signal to each Group fader can be routed to either the L-R mix (via the Pan control) or the C (mono) bus. 100mm Group faders: 10dB of extra gain above the zero mark is provided smoothly and accurately. Each Group is also equipped with AFL.

Master Section:

Connections: The L-R mix and C(mono) bus outputs are balanced XLR with jack insert points. The L-R output mix is also provided on two pairs of balanced jack outputs and one pair of RCA/phono outputs. In addition, a balanced XLR input is provided to allow a talkback mic to be connected; the RCA/phone output is useful for 2-track devices (ie: Tape/DAT record) Metering: Three 12-segment Peak reading bar graph metres display L-R and C (mono) bus output signals. Matrix assignment: Individual rotary dials can route the four Group masters and the Left, Right, and C(mono) buses to any of the four matrix outputs. Talkback: There are four push buttons to route the talkback signal to the Groups, Aux 1&2, Aux 3&4, Aux 5&6, and Aux 7&8. A rotary dial controls the talkback level. Stereo Returns: Two returns (unbalanced jacks on rear) are provided, each with its own rotary dial to control the level and a push button to control where it is routed. Stereo Return 1 can be routed to either L-R or Group 1&2; Stereo Return 2 can be routed to either L-R or Group 3&4. Rec/Alt Output: This record output consists of two channels (L&R) with an RCA/Phono jacks and a 1/4" jacks. It has two pushbuttons, the C switch feeds the C(mono) signal to both L&R channels, the MONO switch sums both the left and right channels together. Also provided is a limiter with a pushbutton to activate ON/OFF and an LED indicator to show when the limiter is active. Monitoring: The 2TK inputs, C(mono) bus, or L-R mix can be selected for the control room outputs and headphones. Rotary dials control the levels. The 2TK inputs can also be added to the L-R mix via the 2TK to mix button.

Dimensions:

Frame Size 12 Channel 16 Channel 24 Channel 32 Channel 40 Channel Width 730mm (28.73") 842mm (33.13") 1065mm (41.93") 1300mm (51.17") 1523mm (59.96") Height 169mm (6.65") 169mm (6.65") 169mm (6.65") 169mm (6.65") 169mm (6.65") Depth 656mm (25.85") 656mm (25.85") 656mm (25.85") 656mm (25.85") 656mm (25.85") Weight 20kg (44.1lbs) 22kg (48.5lbs) 27kg (59.5lbs) 32kg (70.5lbs) 37kg (81.6lbs)

Technical Data:

Noise Measured RMS, 22Hz to 22kHz Bandwidth Mic E.I.N. @ unity gain,150W source impedance -----------------------------------Mix Output, 40 inputs routed to mix -----------------------------------------------------Group Outputs ---------------------------------------------------------------------------------Aux Outputs ------------------------------------------------------------------------------------Matrix Outputs ---------------------------------------------------------------------------------Crosstalk (@1kHz, typical) Input Channel Mute ----------------------------------------------------------------------------Input Fader cut-off -----------------------------------------------------------------------------Pan isolation -------------------------------------------------------------------------------------Mix route isolation ------------------------------------------------------------------------------Group route isolation -------------------------------------------------------------------------Adjacent channel crosstalk ------------------------------------------------------------------Group to Mix -------------------------------------------------------------------------------------Aux Send pots offness (typical) --------------------------------------------------------------Matrix Send pots offness (typical) -----------------------------------------------------------128dBu <-82dBu <-83dBu <-80dBu <-89dBu
<-97dB <-95dB <-77dB <-97dB <-97dB <-99dB <-89dB <-84dB <-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 200 W Input & Output Impedances Mic Inputs ------------------------------------------------------------------------------------------- 2k Line Inputs and Stereo Returns -------------------------------------------------------------- 10k Input channels Insert Return --------------------------------- 5k W with EQ in, otherwise 3k Mix, Group, Aux, Matrix & Direct outputs ----------------------------------------------------- 150 Insert sends -------------------------------------------------------------------------------------------- 75 Recommended Headphone Impedance ------------------------------------------------ 50 - 600

W W W W W W

Connections:
Mono Connection Rear View :
INSERT (1/4" TRS Jack) Tip Return Signal Ring Send 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 Ground Sleeve Chassis The DIRECT OUTPUT is normally post fader. Pressing the PRE button switches it to preEQ, pre-mute, pre-fader.
Stereo Connection Rear View:
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 T/B MIC (3-pin female XLR) Pin 1 Ground Pin 2 Signal Hot Pin 3 Signal Cold MIX L, R & C OUTPUTS (3-pin male XLRs) Pin 1 Chassis Pin 2 Signal Hot Pin 3 Gnd
Master Section Rear View:
MIX L, R & C INSERT POINTS (1/4 TRS Jacks) Tip Return Signal Ring Send Signal Sleeve Chassis L & R MONITOR OUTPUTS (1/4 TRS Jacks) Tip Signal Ring Gnd Sleeve Chassis GROUP 1-4 OUTPUTS (3-pin male XLRs) Pin 1 Chassis Pin 2 Signal Hot Pin 3 Gnd
GROUP 1-4 INSERT POINTS (1/4 TRS Jacks) Tip Return Ring Send Sleeve Chassis AUX 1-8 OUTPUTS (1/4 TRS Jacks) Tip Signal Ring Gnd Sleeve Chassis MATRIX 1-4 OUTPUTS (1/4 TRS Jacks) Tip Signal Ring Gnd Sleeve Chassis REC/ALT OUTPUTS (1/4 TRS Jacks and RCA Phonos) JACK Tip Signal Ring Gnd 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