The Korg Mono/Poly was an exceptionally unique and powerful analog synthesizer with 4 oscillators capable of 4-voice polyphony or as 4 oscillators stacked in an ultra thick monophonic mode. The Mono/Poly also offered an arpeggiator, fantastic sounding 12/dB filter, noise generator, awesome modulation section and a unique 'X-Mod' section for cross modulation of VCO's. This is a fantastic synthesizer capable of big MiniMoog-ish monophonic lines and simple polyphony.