Electro Harmonix Hum Debugger

There's a little change of sound ( bit of short slapbackdelay), but it's absolutely noise canceling!
Even the oldest humming guitar pu's!

Easy to use, a no brainer really.
Put in your fx loop, not before your preamp!
Dead silence, when you not play :-)

Recently I bought this pedal because my jazzmaster p90 pickups are very loud, and sensitive to 60 cycle hum. The pedal eliminates the hum very well, but does create an odd slapback reverb sound. When I put the pedal in the FX loop, the slapback reduced. Overall I recommend this pedal, because it does it's job very well and doesn't effect your tone too much.