The 531 uses dual VACTROL® optoisolators for smooth, non-destructive gain reduction of excessive high frequency energy. The sidechain contains a three-frequency high-pass filter, rather than a narrow band-pass filter, for isolating sibilance. This method ensures that sibilants occurring above the selected frequency are effected without prejudice. Voices that produce sibilants at different frequencies can be effectively processed without hours of tedious knob twiddling.
The extreme surgical approach of many de-essers throughout the checkered history of the breed has been thrown out, and a more simple and musical approach has been taken.
The enigmatically named frequency positions X, Y, and Z follow this philosophy. For those who must know, the -3dB points are approximately 3.275Hz (X), 4.803Hz (Y), and 7.205Hz (Z). Remember, those numbers are approximate.
The X10 switch acts as a range multiplier for the sidechain sensitivity, making fine tuning easier over a large operating range.
The IN switch simply activates the sidechain, making bypassing completely silent.
A handle is provided for easy removal from the rack.
The XQP 531 comes with a ten-year warranty.
531 Data Sheet (pdf)
531 Schematic Diagram (pdf)
Explaining the 531 (video)
