The SPL PQ Master Equalizer is a fully parametric, dual-channel five-band equalizer. The PQ Mastering Equalizer

The PQ based on SPL's 120 V Rail Technology. All five bands can each be activated or deactivated and you got the possibility (for every single band) to separately switch between Constant Q and Proportional Q. This kind of circuit has not yet been achieved in any other equalizer. Several details of this revision were adjusted to current requirements. Each channel can completely be activated or deactivated, thanks to Auto-Bypass, even automated in a freely selectable time frame. Bypass of each band and constant Q of the left side can be controlled by the right side in Link mode.

Another highlight is the possibility to boost or cut the amplitude to 20 dB. If you only wish minor changes of the music material, you can reduce the intensity of the boost or cut by using the 1/4 Gain-Switch, which regulates the potentiometer from max ±20 dB to ±5 dB cut. This gives you the possibility to perform small corrections, as common in Mastering or higher amplitudes in Proportional-Q mode. Thanks to detent potentiometers, a precise recall is very easy to realize. You can adjust parameters Gain, Frequency and Q in 41 steps with detent potentiometers.