Prophet-600
The Prophet-600 is a 6-voice polyphonic analog synthesizer with a 5-octave, 61-note (C-C) keyboard. Each voice consists of two VCOs, two VCFs, and two VCAs. Each of these components has its own independent ADSR envelope. Each Prophet-600 voice uses 2 sets of Curtis Chips for its architecture. The sound originates in a pair of Curtis 3340 VCOs, each with independent on/off switches for sawtooth, triangle, and pulse waveforms. VCO1 can be synced to VCO2. Both oscillators are set with a frequency knob that is notched in semi-tones, with a separate fine tune knob for VCO2. Portamento is adjusted by a single knob. The sound then passes through a pair of Curtis 3372 chips. Each 3372 contains a VCF, a VCA, and a separate volume control for mixing. The VCF is a resonant 24dB/octave filter, with its own ADSR and knob for frequency. The frequency knob is quantized into steps, not allowing you to change it smoothly. Key follow can be set to full, half or off. The LFO can modulate the oscillators (both at the same time), the filter frequency, and the pulse width on the oscillator.
The Prophet-600 has mono mode with chord memory as well as two one-track sequencers and an arpeggiator. The sequencers are programmed in real-time and cannot be edited. The arpeggiator can be set to the normal up or down modes or can cycle through the keys in the order that they were played.