PAiA built the Proteus 1 during the golden age of affordable home synthesis, and it stands as one of the few semi-modular monosynths from that era that actually delivered on the promise of deep sound design without requiring a degree in electronics.
The Proteus 1 is built around two Curtis CEM voltage-controlled oscillators that generate saw, pulse, triangle, and sine waves, with the second oscillator offering pulse width modulation and noise capabilities for texture layering. A single low-pass filter with 24 dB per octave rolloff handles the subtractive filtering, while one LFO provides modulation sources for both oscillators and the filter. The synth features 16 memory locations for storing patches, which was genuinely useful for a monosynth of its generation. The three-octave keyboard lacks pitch and mod wheels, but the real magic happens at the rear patch panel, where you get voltage control over VCO1 pitch, VCO2 frequency modulation, transpose, and filter parameters, making it genuinely modular-friendly. The 1V/Oct protocol means you can integrate it seamlessly into a larger modular setup or control it from external sequencers and controllers.
The Proteus 1 has developed a quiet cult following among vintage synth enthusiasts and modular musicians who appreciate its straightforward architecture and the particular character of those Curtis chips. Finding one in working condition is genuinely rare, which speaks to both its durability and the fact that PAiA didn't manufacture them in huge numbers. It's the kind of synth that rewards patient exploration of its patch panel rather than chasing preset sounds, making it ideal for players who think of synthesis as a hands-on craft.
