• Clone of the Sequential Circuits Prophet-600 (1982)
• Desktop Synthesizer
• Analogue
• 8 voices polyphonic
• 2 oscillators (sawtooth, triangle, square with PWM)
• Hard sync for oscillator 2
• Filter and oscillator FM
• Unison mode with detune
• Noise generator
• 24dB Lowpass filter
• Poly-Modulator
• 2 ADSR envelopes
• LFO with 6 waveforms
• 400 memory locations
• Arpeggiator
• Sequencer with 2 patterns
• Filter CV-In
• USB/MIDI inputs

The synthesizer

The two assertive oscillators, each based on a CEM3340 chip, each have sawtooth, triangle and square waveforms and pulse width controls. Oscillator A can be synchronized to oscillator B. Both VCOs are combined in the mixer, here you also find the noise generator. The nice basic sound is processed with a characterful 24dB Lowpass filter, which is also known as Curtis VCF. It behaves similarly to a Moog filter but sounds different from the transistor cascade due to the IC CEM3320 used. The lower half of the knob deals with the modulation section.

Poly-Mod is composed of the sources Filter Envelope and Oscillator B and is applicable to the frequency of Oscillator A and the Cutoff . This is also where the somewhat harder sounds for the oscillator and filter FM are created.

The LFO provides a total of six waveforms of two sets each and is finally dosed via the modulation wheel of a connected MIDI keyboard. The frequency and pulse width of the oscillators A and B as well as Cutoff are available (simultaneously) as targets.

The two ADSR envelopes are permanently assigned to filter and VCA. Thanks to a total of 400 memory locations, no sound idea is lost anymore.

Sequencer & Arpeggiator

The ingeniously simple sequencer gives access to two patterns, each of which can be up to 400(!) steps long; rests can also be programmed. The notes for this are played via a connected MIDI keyboard. After input, the patterns can be transposed with the keyboard. The arpeggiator primarily offers the playback modes Up, Down, Up & Down, Assign and Random. Synchronization to other equipment is done via the analogue clock input or MIDI/USB.