5 function buttons, HOLD, CHORD MEMORY, UNISON, UNISON/SHARE, and POLY. HOLD acts as a damper pedal would. UNISON is the default monophonic mode where all oscillators are stacked as one. UNISON/SHARE stacks all oscillators until more than one note is played, at which time up to 3 of the oscillators can break away to play the extra notes as needed. POLY mode allows polyphonic playing up to four notes, only one oscillator per note regardless of the number of notes played. CHORD MEMORY can memorize up to a four note chord, allowing the user to play that chord monophonically along the full keyboard range.