Digitech Studio Vocalist

Generates up to four harmony vocal parts (in addition to live voice), based on chords from MIDI keyboard, or can be programmed for harmony.  Live -- operates in real time when driven from MIDI. . 

Has special effects, like chipmunk or gutteral (devil voice).  These are also live, but don't require MIDI keyboard or programming -- just select effect wanted.  Other effects.  Manual included. 

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