234S Stereo 2/3-Way, Mono 4-Way Crossover

The dbx 234s splits one full-range signal into separate frequency bands and sends each band to the amplifier feeding the right loudspeaker. Rather than asking one amp to reproduce everything, subs get lows, tops get highs, and each driver stays inside the range it handles well. You get more usable output from the same amplifiers and far less distortion when the system is pushed.

Filtering uses 24 dB/octave Linkwitz-Riley state-variable filters, the standard for loudspeaker management, which hold a flat summed response through the crossover point. Mode switches configure the unit as stereo 2-way, stereo 3-way, or mono 4-way, so one box covers a small two-way PA, a three-way main system, or a large mono rig. An x10 range switch on each channel multiplies the front-panel frequency markings, covering 45 Hz to 960 Hz or 450 Hz to 9.6 kHz.

Every output has its own level control for matching amplifier sensitivities and a phase invert switch for correcting driver alignment at the crossover point. A 40 Hz high-pass filter on both channels keeps subsonic energy out of the system, and the LF Sum switch combines low frequencies into a single mono subwoofer feed, the usual configuration for live PA.

Connections are 1/4" TRS, differentially balanced on inputs and outputs. Stereo and mono status LEDs confirm the selected mode from across the rack, and per-channel LEDs show low cut and x10 status so nothing gets left engaged by accident. Frequency response runs from under 3 Hz to over 90 kHz with dynamic range above 106 dB, so the crossover shapes the system without adding character of its own. The 1U chassis weighs 4.0 lb.