The latter was implemented by mixing the four footages in a specific proportion, using a rough approximation of a Walsh function. Other controls included the ability to turn each of the footages off and on individually, or to select a pseudo- sawtooth waveform. The filter was a four- pole design based on an SSM circuit, and was in itself highly thought of. This was a step backwards from the Poly-61 architecture, and it ended up being a disadvantage compared to competing products from Roland, Akai, SIEL, and others. Since the MSM5232 did not have any onboard filters, this meant that the only way to implement a voltage controlled filter capability was to provide a single, paraphonic VCF for the combined output of the eight voices. Rather, it combined the signals at a given footage for all eight DCOs and had an output for each footage. (The chip actually had onboard envelope generators, but the Poly-800 did not use them.)Īn unfortunate characteristic of the chip was that it did not provide an individual output for each DCO. Envelopes for the VCAs were generated in software.
KORG POLY 800 SYSEX PATCH
The chip provided the equivalent of a voltage controlled amplifier capability for each voice the synth's patch parameter control system fed in a control signal which controlled the amplitude of each DCO, and could also turn individual DCOs on and off.
The DCOs were divided into two groups of four, each of which was clocked by an external master oscillator. The MSM5232 implemented eight digitally controlled oscillators, or DCOs, each of which generated square waves at four octave-interval footages: 2', 4', 8', and 16' it produced no other waveforms. This resulted in several peculiarities in the voice architecture. In order to cut costs, the Poly-800 was based on a video game tune chip, the Oki Semiconductor MSM5232. In Korg's lineup of polyphonic synths at the time, it was intended to be the low-cost unit, slotting in at the bottom of the price curve below the Poly-61. Korg Poly-800 original version, courtesy of Ī 1980s-era polyphonic analog synth from Korg.