A matrix circuit at the input makes it possible to convert to and process 4-channel surround . The 4CH IN switch is used to activate this circuit. The input matrix can also be used to create a LFE channel. A summed signal from the three front channels is routed to a low-pass filter with an adjustment range from 20Hz to 220Hz.

All connectors are on the rear panel of the unit. In the standard version, the input and outputs are electronically balanced, optionally; the device can be also supplied with balanced and floating inputs and outputs, with high-quality, oversized, toroidal transformers. Balanced and floating inputs and outputs will process signal levels up to +30dBu.

The inputs and outputs are on XLR connectors. In addition, 25-pin SUB-D connectors are wired in parallel to the XLR connectors, which allow simplified connection to the adt-audio Dynaround and Director surround dynamic processor and controller system.

Six, tri-color LED's are used as the peak meters for the separate channels, with a display range from -20dB to +5dB.