SPL PQ - Stereo 5-Band Mastering Equalizer (All Black)The PQ Mastering Equalizer is a fully parametric, dual channel five band equalizer. It is a new revised edition of the well known SPL PQ Mastering Equalizer Model 2050. These units are based on SPL's 120V Rail Technology. The new PQ features the same high quality characteristics as the previous model. All five bands can each be activated or deactivated and you have the possibility (for every single band) to separately switch between Constant Q and