CRUMAR STRATUS Vintage CEM Synthesizer

Crumar Stratus CEM-based vintage synthesizer, 1982. Recently serviced it looks and sounds great. Professional packing and fast shipping guarantee.

Unfairly marked as "slimmed-down version of the Crumar Trilogy", the Stratus is actually a synth with its own character and features, a hybrid keyboard with a set of sounds which belong neither to the world of the conventional organ nor to that of complex polyphonic synth. Released in 1982, it's a 6-voices polyphonic analog synthesizer + organ synth which can be played separately or simultaneously.
 
SYNTH SECTION

The Synth section implements two 74LS221 oscillators (the same used in the ultra-rare Crumar DS-1) with saw, square and saw+square waveforms. The two oscillators can be synced or tuned separately. The Synth architecture is basically built around CEM chips and in fact it features 6 CEM VCFs, 6 CEM VCAs and 6 CEM EG (one per voice). The CEM filters and envelopes, combined with the various oscillator features, make it possible to create a wide range of electronic pianos, lush strings, quasi-vocal pads and tuned percussive sounds. A very unusual (unique?) feature is the "Alternate" switch: this automatically switches between sawtooth and square on every key depression, or only after all the keys have been released and one is depressed again.

ORGAN SECTION

The Organ section implements two additional detunable (or syncable) master tone generators divided-down to generate the octaves of the 4 horizontal drawbars (2', 4', 8' and 16'). The fact that the two master Organ oscillators can be detuned allows to produce a vast, rich, organy sound. The Organ section is fully polyphonic and can benefit of the Glide effect and the LFO features. The Organ audio output can be taken separately from a ¼inch jack socket on the back panel, or from the socket marked 'Polysynth' which in fact gives a mix of synth and organ if used alone.

Synth Specifications :

- 6 Note polyphony
- 2 DCO's : Saw, Square, Saw+Square
- Osc Fine tune x 2
- Osc Octave Down x 2
- Filter Low-Pass Cutoff + Resonance
- Filter Envelope Depth/Polarity
- Glide : Amount + Speed + Directions + Mono/Poly
- ADSR Envelope : same for Volume / Filter
- LFO : Pitch / Volume / Filter
- LFO Ctrl : Amount / Speed / Attack / Delay
- LFO Shape : Saw/Square
- LFO Reset : Mono/Poly

Organ Specifications :

- 2 Master DCO's
- Osc Fine tune x 2
- Osc Octave Down x 2
- 4 Organ Drawbars
- LFO : Pitch / Volume / Filter
- LFO Ctrl : Amount / Speed / Attack / Delay
- LFO Shape : Saw/Square
- LFO Reset : Mono/Poly
- Glide : Amount + Speed + Directions + Mono/Poly

Outputs :

- Polysynth Output
- Organ Output
- Pedal Ctrls : Release + Sync + VCF