Crumar Stratus

When Crumar released the Stratus in 1982, they created something genuinely unusual: a hybrid that treats the organ and synthesizer as equal partners rather than an afterthought. This Italian-made machine sits at an interesting crossroads between the polyphonic richness of a drawbar organ and the sonic flexibility of a proper analog polysynth, and it does both without apology.

The Stratus packs a 49-key keyboard with two distinct sound engines that can be mixed together or routed to separate outputs. The organ section delivers full polyphony across four drawbar footages (16', 8', 4', and 2'), while the synth side offers six-voice polyphony with dual digitally controlled oscillators capable of sawtooth, square, or mixed waveforms. The synthesis architecture is straightforward subtractive: each voice runs through a resonant low-pass VCF, envelope generator, and VCA, all built around the same premium CEM chips found in far more expensive polysynths of the era. The control panel features 26 knobs and four horizontal sliders, giving you direct access to oscillator tuning, filter cutoff and resonance, envelope parameters, and a four-mode glide system that lets you choose how each oscillator responds to pitch changes. An LFO modulates the filter and VCA, and you can control the filter externally via pedal input. The machine weighs 18 kilograms and measures 88 by 48 centimeters, making it reasonably portable for a keyboard of this capability.

The Stratus has developed a quiet reputation among players who appreciate its particular strengths: the ability to layer thick organ chords with synth textures, the interesting harmonic possibilities when oscillators are detuned or synced, and the characterful filter response that gives abstract sounds real personality. The trade-off is that the six-voice architecture uses a clever but limiting design where notes in the same octave and their tritones share processing chains, meaning lower notes can retrigger when you play higher ones. This quirk becomes a feature once you understand it, but it's worth knowing upfront.