MXR M-89 Bass Overdrive Pedal The MXR Bass Overdrive is an original design that delivers warm, tube-like overdrive. Along with standard Volume, Tone, and Drive controls, this pedal features a Clean control so you can blend a pre-set EQ clean signal with the overdrive signal, resulting in sweet, burly bass overdrive. Featuring a unique overdrive circuit designed specifically for bass with separate clean and drive controls for tonal versatility, and 100% analog circuitry for rich, warm tone.