The original MXR ZW44 Zakk Wylde Overdrive
 
We profiled with a bunch of different settings on all knobs.
 
Features/Specifications:
Input Impedance: 1meg Ohm
Nominal Input: -22dBV
Output Impedance: < 7.5K
Ohm Output Level: -22dBV
Signal To Noise All Controls @ Mid Position: >88dB 'A' weighted
 
Have Fun!