A polyphonic synth introduced by Korg in 1982. It marked a milestone in technical advancement as it was the first polyphonic synth with patch memory to sell for under $1000 US, making it affordable to a wide swath of performers who had not had access to a polyphonic synth previously.
As the name suggests, the Polysix is 6-voice polyphonic, using voice allocation to assign voice circuits to played notes. Each voice consisted of a single voltage controlled oscillator with a suboscillator, a lowpass voltage controlled filter, a voltage controlled amplifier, and an envelope generator. A single low frequency oscillator was assignable to modulate VCO frequency, VCF cutoff frequency, or VCA output level. A five-octave keyboard plus pitch and mod wheels were provided. The "chord memory" feature from the Mono/Poly was carried over, allowing the performer to play a memorized chord in any key by playing the root note.
The built-in arpeggiator was one of the most advanced of its day, providing several choices of patterns plus the ability to memorize and use a note pattern played by the performer. It had a dedicated LFO for clocking, or it could be synced to an external clock. The synth also contained built-in effects, including a phaser and several chorus-type effects. 32 patch memory locations were available, and the synth had a cassette interface for backing up and loading patch data. No Polysix ever came from the factory with MIDI, although Korg later offered a retrofit. Today, MIDI retrofits, more capable than the Korg one, are available from third party suppliers.
The Polysix set the pattern for the lower-cost polyphonic synth arena that the Japanese manufacturers, notably Roland, would compete for in the mid-1980s. These were a driving force behind the New Wave synth pop music of that era, and were widely used by New Wave bands.
One thing to watch out for when considering a vintage Polysix is that the patch memory was backed up by a nickel-cadmium battery. In nearly all cases, unless they were replaced within the first few years after manufacture, these leaked and damaged the CPU board that they were mounted on. Repair is sometimes possible, but the prospective purchaser should get a tech to examine the unit before buying.