http://www.godlyke.com/maxon-guitar-effects/fuzz-elements-pedals/fv10-fuzz-elements-void
Guitar Effects Pedal Demo - Maxon - Fuzz Elements - VOID
Based on the rare Ampeg Scrambler, the FV10 generates lots of even-order harmonics that can then be mixed with the dry guitar sound. These overtones are dynamic and frequency dependent, changing constantly with input signal. True Bypass Switching.