TK Audio’s best-selling 500-series module, the BC501, is a stereo bus compressor that features all the power of TK’s flagship BC1-S. The new BC501 adds some more functions taken from the BC2-ME mastering compressor, such as additional ratio settings (1.25:1, 6:1), a THD switch that adds more even harmonics to the signal, and three HPF settings from which to choose (80Hz, 150Hz, 220Hz). All controls are stepped for easy, precise recall. A dedicated Dry/Comp knob allows blending between the original and compressed signals, and an external sidechain input (accessible via stereo 1/8″ mini TRS jack) is also provided.