The SK30 is a 7 voice Polysynth that also featured Organ and String section – a Combo Synth. A feature rich synth of it day, with aftertouch as well for modulation options – it’s Yamaha’s answer to the Moog Opus 3 or Arp Quadra. Much of the technology, design and layout is shared with all the other ‘CS’ series of that time including the CS70M etc. The Polysynth is pretty punchy and the distinctive ‘CS’ resonant filter makes this a unique sounding instrument….al la CS50/60/80.
Yamaha's SK30 is a combo-keyboard with synthesizer, organ, brass and string sections. The SK- 30 was released in 1980. Very sturdy casing, 4-octave and fully polyphonic the features also include a leslie simulator, vibrato, attack and sustain rocker switches, a slider for 'brilliance' and a one-octave transpose switch. Not exactly feature-laden, but a lovely string synth sound. Interestingly, they are often referred to as 'analog', but in fact do have a digital section. Its organ has one of the early implementations of Yamaha's FM technology in a very limited form, concurrent with the GS-1/2 development platforms which eventually led to the DX series.
The ORGAN SECTION is available in all the SK series synthesizers. It offers a full range of stop levers from 1' to 16', percussion levers with adjustable decay, and controls for overall sustain, brilliance and decay. This gives you quite a lot to work with in the way of synthesis. The organ's sound is FM based and it sounds very B3 like. You can add a Vibrato and a noisy but good Tremolo to it. Its sound is all about the 70's era rock organ, especially with the Ensemble chorus effect in use. It also has a Leslie-speaker output around back.
The PRESET STRINGS section isn't very sophisticated and offers very limited editing capabilities. It is the string section though, that is worth aquiring this keyboard for. Very similar to the best of the string synths, (such as the Arp Solina/Omni or the Logan String Machine) it has a sound reminiscent of the opening of 'Oxygene' (J-M Jarre) or the lead line from 'Love Will Tear Us Apart' (Joy Division).
The SK30 includes the POLY-SYNTH SECTION: a 7-note polyphonic synthesizer with basic filter, pitch, envelope, and portamento controls. It features two (detuneable) oscillators per voice so it's good for thick pads. It lacks any bite whatsoever and, even in normal attack mode, has way too slow an envelope to be used for any bass or percussion sounds. But, the pads and strings you can get certainly shine and glitter like Bowie a-la Ziggy Stardust (especially when layered with the Strings section). It's like a good entry-level synthesizer. Basic and simple LFO, filters and ADSR envelopes. It has a built-in sustain and the Tremolo and Ensemble chorus effect also apply to this section.
The SK30 also featureS a SOLO SYNTHESIZER SECTION which is a single VCO driven mono-synth similar to a Roland SH-101. It has basic pitch, waveform, filter, volume, envelope generator and portamento functions. Its resonant filter isn't great and can't be driven into self-oscillation. The keyboard's after-touch can control the vibrato, tremolo, and brilliance effects. You can effectively play leads in the solo section while simultaneously playing chords in the string, organ or poly-synth sections.
