The RB-DA4x5 is a 1U rack-mount combined distribution amplifier and mixer. It has 4 mono analogue audio inputs on female XLR and 4 groups of 5 outputs on 15-pin D-type connectors. Each output group has a front panel 5-way DIP switch which selects which input(s) to route to the output group. This allows each of the four inputs, or a 1kHz tone at 0dBu, to be mixed to the output group.

- 4 input, 20 output distribution amplifier.
- Audio presence LEDs for inputs or outputs.
- Balanced I/O that can be wired unbalanced.
- 1kHz test tone output to check transmission lines.


The inputs and outputs are electronically balanced and can be wired unbalanced. Each input has adjustable gain via a preset potentiometer offering a gain range from -8dB to +18dB. Each output is individually buffered so that a short circuit on one output won't affect the others. The output gain of each group can be similarly adjusted between -8dB and +18dB via preset potentiometers.

The DIP switch settings and gain controls are recessed beneath a screw-fixed front panel cover so that the settings cannot be accidentally altered, for secure applications.

Four bright LEDs on the front panel indicate input or output group levels when the AUDIO PRESENCE button is pressed. The LEDs illuminate green from -12dB to 0dB, orange from 0dB to +6dB and red for inputs and outputs at +6dB and above.