Kawai SX-210 Analog Polyphonic Synthesizer

The Kawai company, which was known for its electronic pianos, launched its first synthesizers SX-210 and SX-240 in 1983 and 1984. They are analog and polyphonic instruments with DCOs for digital control. The smaller DX-210, originally called Teisco, is an 8-voice polyphonic DCO synthesizer with SSM2044 filters per voice. 

The only analog controls are the volume fader, the master tune pot and the pitch bend. The Kawai SX-210 is digitally controlled, but its sound generation is completely analog. Each voice has a DCO, an SSM-2044 LP filter and a VCA. The VCA and VCF each have their own digitally controlled envelope. Sawtooth and square wave with pulse width modulation are available for the DCOs. A sub-oscillator supports the oscillation modes, which can be activated simultaneously. The pulse width of the square wave can be adjusted manually or modulated via the LFO. This has the oscillation forms sawtooth, sine and square. It can affect the DCO, VCF and VCA, which enables tremolo effects. The DCO is supplemented by a noise generator. There is a 4-pole LP filter with an SSM2044. The SX-210 also offers a chord memory, a hold function, a unison mode, pitch bend with postamento, glissando and auto-pitch. It can be set to a poly-4 mode with two DCOs on one key, which can be detuned against each other in semitone intervals. (Source: Amazona)