2-Way/3-Way stereo - 4-Way Mono Active Crossover.2x XLR-Input with 25Hz high-pass filter switch, 6x XLR-Output, high quality 24dB/ octave slope Linkwitz-Riley filters, In/Out level controls, xover frequency selection for all bands, mute key and phase reversal for each band, adjustable delay time up to 2ms for outputs, “LOW SUM” function to convey the whole LF range of L&R channels to a mono sub out, multiband limiter with adjustable threshold