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 way D-type connectors. Each output group has a five way front-panel DIP switch assigned to it which is used to select the input(s) to send to the output group. This enables each of the four inputs, or a 1kHz 0dBu tone, to be mixed to the output group.