PA 1254 is a 150 W @ 4 Ohm 4 channel professional audio amplifier, built in 1 rack unit metal enclosure. It has balanced inputs and outputs with Euroblock connectors. The front panel has a power switch, independent volume controls for each channel, and power, signal, clip and protection indicators. It incorporates nine operating modes, of which two allow the use of channels C and D for the connection of subwoofers with adjustment of the crossover cutoff frequency.