One unit allows you to switch between 10 pairs of speakers and 4 subwoofers. The units can be cascaded to allow you to switch between up to 40 pairs of speakers and 16 subwoofers! Active and passive speakers can be mixed on one unit! The remote control offers a switchable low pass filter for the subwoofers as well as dim and mute functions . All outputs are galvanically isolated and balanced! Each output level can be adjusted by ± 12 dB. The remote control offers a switchable low pass filter for the subwoofers as well as dim and mute functions . All outputs are galvanically isolated and balanced! Each output level can be adjusted by ± 12 dB. In addition the unit provides connectors on the rear for optional display LEDs which can be placed on top of or next to the speakers to indicate which one is selected. All inputs and outputs are equipped with XLR connectors, the passive speaker outputs with Speakon connectors.