This unit has been produced from 1991 to 1997, and it’s not really easy to find an used one. In my opinion the PQ4 is much better than its graphic counterparts (like the GE6 and GE7 from Boss, and other graphic equalizers) because of its flexibility. However, the PQ4 is something that requires a fine tuning to get your sound, and it isn’t a pedal suited to quick-and-dirty settings change: more like a sniper rifle than a shotgun. Concentric knobs don’t help, either.
Specifications:
Residual Noise Level: < -98dBm (IHF-A)
Input Impedance: 1 Mohm
Output Impedance: 1 kohm
Current Draw: 23mA
Recommended Load Impedance: > 10kOhm
Resources