Each channel has a jack input with a parallel output for passing through the signal. An attenuation switch (-30 dB) allows either a line or loudspeaker signal to be connected. Active 4 x DI box, 19 in. format. All connections and switches are located on the front panel, and an additional parallel XLR output is located in back. 19 in. rack-mount format, one rack space, 90 mm front to back.