Zone mixer Allen & Heath GR4

Allen & Heath GR4

Zone mixer Allen & Heath GR4 has four balanced microphone inputs on pluggable terminal blocks. Each mic input shall have independent gain control on rear mounted pots and have a +50 dB gain and global Hi-Level LED indication if any pre level signal is greater than 14 dBu. In addition microphone “1” shall be made switchable to a front mounted XLR connector via a front mounted selection switch.

Features independent control of High and Low frequency band EQ via pots mounted on the rear of the chassis and a 200 Hz HP filter shall be employed via rear mount dip-switches.

There are four stereo unbalanced line level inputs on RCA connectors. Each stereo input shall have an independent level pot with +5 dB trim and global Hi-Level LED indication if any pre level signal is greater than 14 dBu. An additional 10 dB shall be available for low level sources via a PCB jumper. There shall be a priority line level input which will override all other line level sources, however, there shall be the ability to disable this function via a dip-switch. There shall be a front mounted 3,5 mm AUX socket that will have priority over any source wired to stereo input 4.

Obtains two impedance balanced stereo zone outputs on pluggable terminal blocks. Each zone shall have input source selection and variable mic and music level pots. There shall be independent control of High and Low frequency band EQ via front mounted pots and a 3 LED stereo level meter. There shall be internal jumpers to mono zones 1 & 2.

There are further two zones which are impedance balanced mono outputs on pluggable terminal blocks. The 2mix2 to these outputs shall be pre-defined and have no less than six optional mixes selectable via PCB jumpers.

Allen & Heath GR4 accepts remote control inputs via two rear mounted 4-wire pluggable terminal blocks. Each connector will allow analogue control of music source and level via a 0 – 10 v control signal. An additional RJ45 connector shall be present to accept off the shelf wall mounted controllers with a maximum of two controllers connected in daisy chain configuration. Remote control shall be enabled via dip switch.

There shall be an alarm contact closure input on a pluggable screw terminal connector. The input shall be Normally Open (NO) and reversed to Normally Closed (NC) via DIP switch.

Features

• Primary mic mode: When audio sensed on MIC1 channel and/or PAGE contact closure is sensed then music is faded to pre-set level and MICS2-4 muted for the duration of the announcement. MIC1 zone select LEDs flash slowly when in priority mic mode
• Secondary mic mode: When audio is sensed on MIC2, 3 or 4 then music is faded to pre-set level for the duration of the announcement. MICS 2-4 zone select LEDs flash slowly when in secondary mic mode
• Emergency mic mode: When alarm contact is activated all zone feeds are muted and Mic1 is fed direct to all zones. All select LEDs except mic1 LED are switched off for the duration. Mic1 LED will flash quickly
  Juke box mode: When music sensed on ST3, fade down current music feed and fade up ST3. When ST3 silent for pre-set period, fade down ST3 and resume previous music feed. Mic volume not affected
• Music fade: Option to select next music feed and then unit will fade between sources after short delay
  Zone lock: Allows select buttons to be disabled for a particular zone. LED corresponding to the button locked will be turned off

Connectivity

• Mic inputs. 4 mic inputs on rear mount Phoenix connectors with MIC1 selectable to an optional front mounted XLR
• Line inputs. 4 stereo inputs on rear mount phono connectors. An additional front mounted 3,5 mm jack socket overrides input 4 phono source.
• Zone outputs. Two stereo (mono selectable via internal jumper) zones on rear mount Phoenix connectors. An additional two mono zone outputs are available with mix output being selectable from internal jumpers
• Control. Paging and Alarm contact inputs on rear mounted Phoenix connectors allow integration with 3rd party paging stations and fire alarm systems

Specification

• Mic Input Sensitivity (Gain = Min): 0 dBu
• Mic Input Sensitivity (Gain = Max): 50 dBu
• Mic Level control (Max): +5 dB
• Mic Level control (Min): -80 dB
• Mic HPF -3 dB: 320 Hz (TBC)
• Mic EQ LF: +/- 15 dB fc = 80 Hz
• Mic EQ HF: +/-15 dB fc = 8 kHz
• Mic Frequency Response: 20 Hz – 20 kHz +/-1 dB
• Mic THD+n @0 dBu in 1 kHz: 0,004% 22-22 kHz
• Mic THD+n @-30 dBu in 30dB gain 1 kHz: 0,005% 22-22 kHz
• Mic Hi Level warning LED (Unity gain): +18 dBu
• Clip level (Unity gain): +21 dBu
• ST Input Sensitivity (Gain link OFF): 0 dBu
• ST Input Sensitivity (Gain Link ON): -10 dBu
• ST Level control (Max): +6 dB
• ST Level control (Min): -76 dB
• ST Frequency response 20 Hz: 20 Hz – 20 kHz +/-0,5 dB
• ST THD+n @-10 dBu in 1 kHz: 0,015% 22-22 kHz
• ST THD+n @0 dBu in 1 kHz: 0,035% 22-22 kHz
• Crosstalk from unselected channel: -75 dB @ 1 kHz
• Main Zone Level control (Max): 0 dB
• Main Zone Level control (Min): -74 dB
• Main Zone Hi Lev LED (Unity gain): +18 dBu
• Main Zone EQ LF: +/-15 dB fc = 80 Hz
• Main Zone EQ HF: +/-15 dB fc 8 kHz
• Main Zone Clip level (Unity gain): +21 dBu
• ST Input to Main Zone output (Unity): -90 dBu 22-22 kHz
• Mic Input routed at Min gain as well: -88 dBu 22-22 kHz
• Mic Input routed at Max gain: -77 dBu 22-22 kHz (150 R source)
• Power consumption: 15W
• GR4 unit (no remote attached)
• Dimensions: 48x242x438 mm
• Weight: 3,4 kg