500-series de-esser

The DerrEsser is a dynamic high-frequency filter module in API 500 format: de-esser, high-frequency limiter and high-pass and low-pass filter in one unit. This version has the horizontal faceplate in the current design. An API 500-compatible rack is required for operation.

• Four operating modes: DS (de-esser), HF Limit, high-pass and low-pass
• Level-independent DS mode: the high-frequency content is compared with the low-frequency content, so changing the overall level does not shift the threshold
• HF Limit acts as a high-frequency compressor with a tailored soft knee to smooth harsh highs
• Listen function to monitor the high or low frequency band; low-pass filter with 12 dB per octave
• Corner frequency adjustable with the Frequency knob (active crossover), VCA gain control
• Clip indicator (BAD) and true bypass
• Frequency response 3 Hz to 120 kHz (-3 dB), dynamic range 115 dB, noise floor typically -93 dBu
• Distortion 0.0035% to 0.01% depending on mode and settings
• Balanced input (20 kOhm), single-ended output with balanced impedance (below 51 Ohm)
• Attack below 1 ms, release 0.04 s (fixed internally)
• Power consumption 8 W max., 4 W typical; hand-built and calibrated in the USA