Polyphonic Teensy 3.6 Synthesizer with MIDI Control
The Synthesizer has the following characteristics:
- eight voices
- two LFO (sine,sawtooth,square,triangle) per voice
- two VCO (sine,sawtooth,square,triangle) with multiplier per voice
- one 12dB VCF (lowpass,highpass,bandpass) per voice
- one AHDSR generator per voice
- keyboard velocity
- glissando effect
- arpeggiator effect (three tone chord, major/minor, up/down, variable speed)
- one MIDI input for a MIDI keyboard
- one MIDI input for a MIDI controller like https://github.com/ErikDorstel/midiKnobs
The project uses the Teensy Audio Library to implement the synthesizer components like VCO, LFO ... . This graphic shows the connections of the components used.
The octoTron source code uses a new feature in the audio library. To restart an LFO with an absolute phase angle, the file synth_waveform.h must be changed. This pull request contains the changes needed PaulStoffregen/Audio#275 .
The hardware used is very similar to https://github.com/ErikDorstel/stringFlow . The only difference is the use of a second MIDI In port. The octoTron Synthesizer use this second MIDI In port to connect a MIDI controller. The assigned MIDI controller numbers and the schematic are part of the documentation.
