The MTC-SB210-SAT adds an internal subwoofer crossover. This module accepts either mono or stereo input. The crossover network routes low-frequency signals to the SB210 drivers and routes mid-frequency and high-frequency signals to two (in stereo mode) or to one (in mono mode) satellite output jacks for connection to satellite loudspeakers. MTC-SB210T allows the SB210 to be driven from a 70V or 100V distributed loudspeaker line. This module accepts either a mono or stereo input, with a total maximum power capability of 250 Watts. MTC-SB210T-SAT combines the above two modules, allows the SB210 to be driven from a 70V or 100V distributed loudspeaker line AND contains an internal crossover that routes the low-frequency signals to the SB210 drivers and routes the mids and highs to satellite output jack(s) for connection of external low impedance satellite speakers.