BOSS PQ-4 PARAMETRIC EQUALIZER

THE PQ-4 is quite rare. No longer made and are quite sought after. You can adjust Presence, Low Level boost or cut, Mid Frequency range between 100Hz and 1.6 KHZ , and a High Frequency range between 500HZ and 8KHZ. Each frequency range selector has it's own individual levels for boosting or cutting specific frequencies, plus it has a -18 to +18 over all level boost or cut.