Up for sale, a 1980s Korg Mono/Poly MP-4 synthesizer in excellent condition and in perfect working order. The Mono/Poly is a 44 key "mono-polyphonic" analog synthesizer manufactured by Korg from 1981 to 1984. This model is the sister synthesizer to the Korg Polysix, with four highly stable voltage-controlled oscillators (VCOs), a 4-pole, self-oscillating low pass filter (LPF), several modulation capabilities, and pseudo-polyphony (paraphony) functionality.

The four VCOs can be shared in four-voice Polyphonic mode, or linked in Unison for a versatile monophonic lead. Each VCO has its own level, tune, and waveform type control. Waveforms include triangle, sawtooth, and variable pulse wave. It has a great VCF (filter) section as well as two envelope generators (one for the oscillators and one for the filter), and there are also two individual LFOs which can be used to modulate the Pulse Width, Envelope, and Arpeggiator independently.

A very flexible and fun synthesizer, other cool tricks up Mono/Poly's sleeve include chord memory and an effects mode in which oscillators have a variety of ways to be synced. The built-in arpeggiator and sequencer can run all 4 VCOs at a time or cycle through each voice per note. There's also portamento, CV/Gate, VCF, and VCO mod inputs, a white noise generator, and the pitch/mod wheels can be assigned to control LFO, pitch, or the filter.

Cosmetically, this synthesizer is in great shape, with some light scuffs and marks from use at the corners of the wood framing the keyboard. All original knobs are intact, as are the four rubber feet on the bottom of the enclosure.

Features:

• Analog, Subtractive Synthesis
• Oscillators: 4
• Waveforms: Pulse, Saw Down, Square
• Osc Modulation: Envelope, Keyboard, LFO, Mod Wheel, Pitch Wheel
• Envelopes: 2
• Envelope Parameters: Attack, Decay, Sustain, Release
• Filters: 1
• Types: 24dB Slope (4-pole), High Pass, Low Pass, Resonance
• Filter Modulation: Envelope, LFO
• LFO Parameters: Triangle
• Polyphony: 4
• Timbrality: 1
• Tuning: Standard
• Modes: Mono, Polyphonic
• Patches RAM: 1
• Storage: Internal
• Arpeggiator