OVERVIEWA classic overdrive circuit with modern modifications for improved performance and versatility. The MXR M77 Custom Modified Badass Overdrive Guitar Effects Pedal is a classic overdrive circuit with modern modifications for improved performance and versatility. For added flexibility, there's a 100HZ cut and boost control that allows for a more focused EQ when cut, or a beefier tone when boosted. The Bump switch engages an alternate EQ voicing that boosts the lows and mids. Put it in fr...