Korg Sigma

Back in 1979, this synth broke new ground by splitting its brain into two distinct engines—Synthe for raw waveform tweaking and Instrument for instant organ-style presets—letting you layer them on the fly for sounds no other preset box could touch.

Its subtractive analog heart pumps through two VCOs delivering saw, pulse with PWM, square, sample-and-hold, and noise, all feeding into independent 12dB/oct highpass and lowpass filters you sculpt with a pair of expressive joysticks—one also handling pitch bend, vibrato depth, and noise mix. The 37-note touch-sensitive keyboard adds monophonic aftertouch that routes to pitch, vibrato, or section balance, while organ-tab switches select from 11 Instrument and 8 Synthe presets, stackable for thicker tones, plus a ring modulator for metallic bite and CV/gate/trigger ports for modular integration. At 774 x 400 x 173 mm and 11 kg, it's a sturdy live performer with separate mono outs for each section and a headphone jack.

Vintage players dig its quirky joystick immediacy and stacking tricks that punch above monophonic limits, though some note the presets feel basic without deeper editing—still, its weird charm has earned a cult following for bold, hands-on analog grit.