Check the listing for details. MXR Uni-Vibe M68 Chorus/Vibrato Guitar Effects Pedal. Condition: New. Listed at 159.99 USD. The M68 Uni-Vibe chorus/vibrato is one of the most iconic effects in music history. Since the late '60s, groundbreaking guitar players have used it to expand the tonal and textural palette of the electric guitar. The MXR team has just remastered the classic effect for modern players. The MXR M68 Uni-Vibe chorus/vibrato delivers the same chewy, Leslie-sounding goodness with a smaller footprint. With its simple three-knob interface, you can dial up the iconic effect to your taste in short order. First, use the VIBE switch to select either Chorus Mode-dry signal mixed with pitch-shifted signal-or Vibrato Mode-only pitch-shifted signal. Then, use the LEVEL control to set the effect volume, the SPEED control to set the sweep rate, and the DEPTH control to set overall intensity.