The 223s from dbx is a dual channel, stereo 2-way or mono 3-way crossover. A crossover is essential for efficient PA operation because it filters the full band input signal into specific frequencies that match a speaker's optimum frequency-reproduction range. This leaves the amplifier free to use its full power on the usable signal, eliminating distortion and delivering clear sound.
The unit features Linkwitz-Riley 24dB per octave filters, independent output gain controls for level matching, output phase inversion, 40Hz low cut filter, and optional mono summing of the low frequency (subwoofer) output. Quality components and meticulous attention to detail offers exceptional sound and rugged reliability, while exuding great precision from the solid "click" controls to the high quality 1/4" TRS inputs and outputs.

Stereo 2-way, mono 3-way crossover
Mode switch for stereo 2-way or mono 3-way operation
24dB per octave Linkwitz-Riley filters
Low frequency summed (subwoofer) output
Range switch on both channels (x10)
40Hz high-pass (low-cut) filter on both channels
Phase reverse switch on all outputs
Individual level controls on all outputs
Stereo/Mono status LEDs indicate the selected mode
1/4" TRS differentially balanced ins and outs
CSA NRTL/C approved and CE compliant