Maxon OD-9 PRO+ Plus OverdriveThe Maxon OD9 Pro Plus Overdrive Pedal may look just like your old favorite, but that's where the similarities end. With improved circuitry, the OD9 overdrive stands at the forefront of the Nine Series effects evolution. The OD9 overdrive pedal uses a signal distorting diode (Panasonic #MA150) that is located in the amplifier stage's negative feedback loop (this stage also contains the JRC4558 IC chip). Therefore, the OD 9 pedal distorts the signal in