Studio talkback interface with external mic input, 30dB mic gain, routing to three output with priority to production

The CHEF amplifier was designed for conductor, band leaders
1) to provide a good communication system with production manager:
(Talk back to PROD) (TV stage manager) his musicians (Talk back to ORCH) and a third party (ON AIR)( Talk back to FOH)
2) to receive CUES or information from stage manager on an auxiliary input (INTERPHONE)(AUX)
3) getting a broadcast quality stereo program sound.

Features

- Stereo Bargraph VU meters to monitor the level pre fader of master control.
- High quality audio taper Stereo volume control.
- High quality linear control for Balance-Trim control to Left/Right output.
- Power amplifier to headphone up to 10Watts in 8 ohms.
- Universal Switching Power Supply 95V/240 50/60Hz
- Standard IEC AC line input voltage with EMI filter.
- Standard XLR connectors for Input / Output.
- Pin1 Lift on every Input / Output.
- Flange support to fix the "CHEF" on a microphone stand.
- Slide switch, under the unit allows to reduce the gain of the power amplifier by 6db to provide a wider range on the master control.
- Size 7" X 7" X 3.5"
- Weight 2 pounds (1 kg)

Specifications

Communication system
Pro quality MIC preamp gain 30db
Routing to three output with priority to "PROD" (PRODUCTION)

Output selection TALKBACK TO
To PROD : Momentary switch, (Press to talk) on the unit or by FOOT SWITCH
To BAND : Toggle switch, on the unit. A square LED (GREEN) showing.
To ON AIR : Toggle switch, on the unit. A square LED (RED) showing.
Center position : Microphone is OFF

Output Level
To PROD : Line +4db (TRIM)
To BAND : Mic (or custom line +4db)
To "ON AIR" : Mic (or custom line +4db)

Program sound input +4db
High common mode rejection line input buffer for LEFT and RIGHT.(-120db) Maximum input level: +20db

Auxiliary input (Line level +4db NOMINAL) (Interphone) ( AUX)
High common mode rejection ( -120db) line input buffer.
Maximum input level: +20db
The monitoring of this Auxiliary signal will be on the Left BARGAPH VU meter as a Post Fader.
This Auxiliary signal is also used to activate a Ducking circuit.
The user can choose the action of the DUCKER on the Left Program or
have the Auxiliary source to be mixed in the Left program or both.

Here is how it works:
When the toggle switch (near the AUX level control), is set to DIM position, the Left program will be reduced by about 10db, depending on the setting of the threshold control. The AUX signal will then be MIX into the LEFT channel .

When this toggle switch is set to MIX position, the left program is in full dynamics.
The AUX signal is MIX into the Left program source.
Internal jumper will allow the AUX signal to be MIX into both Left and Right channels, for a center source.(Factory set)
Monitoring of the AUX signal will be on both VU Bargraph.

DUCKER
High performance Ducker with fast attack (5ms) slow release (1000 ms factory)
It controls the dynamics of the Left program sound. The AUX signal is used to trigger a DUCKER circuit that will dim or compress the LEFT program by 10db when AUX signal is above threshold level, allowing a more present sound of the AUX signal to the conductor's left headphone.
Threshold setting (-40dbu to +20db) allows the user to adjust the ducking level.

OTHER APPLICATIONS
- Simultaneous translation
- Voice over
- Radio-TV presenter