Tonelux EQ5P - Parametric EQ (500 Series)

The EQ5P from Tonelux is a discrete parametric style equalizer housed in a 500 series enclosure. There are no dedicated Q controls on the front panel, but rather the filter width is internally adjusted based on the boost and cut settings using a "Constant Energy Curve." Also known as "Proportional Q," the circuitry keeps the bandwidth wider at lower boost/cut levels, and becomes narrow at higher boost/cut levels, in the process delivering a musically pleasing result.