The Rotovibe Chorus/Vibrato features Vibrato and Chorus modes and rocker-controlled effect speed to create expressive rotating speaker effects with LED speed indicators. This pedal can be powered by a 9-volt battery, a Dunlop ECB003 9-volt adapter, or the DC Brick™, Iso-Brick™, and Mini Iso-Brick™ power supplies (not included). THE LONG STORYThe Rotovibe Chorus/Vibrato simulates the rotating speaker sounds popularized by Hendrix and many others. This is a very expressive effect thanks to its built-in real-time control. Choose either Chorus or Vibrato, adjust the intensity of the effect, and then control the effect's speed by rocking the pedal back and forth.