Used API 550B Rack Equipment

Used API 550B rack-mount equalizer in good condition, featuring classic 3-band EQ with five selectable frequencies per band and ±12 dB of boost/cut. Known for its punchy, musical tone, the 550B uses proprietary API 2520 op amps and utilizes fully discrete circuitry. Ideal for tracking or mixing with that signature API sound, this industry-standard unit fits standard 500-series racks and operates reliably in any professional audio environment.