Poly Analog
Polyphonic virtual analog synth based on Daisy Seed
This is a project I’ve been working on for a long time… and now it’s ready!
A few years ago, I discovered the Daisy platform by Electrosmith, and it completely blew my mind. As an audio developer, it instantly gave me tons of ideas for synths and audio FX projects.
One of them was to design a polyphonic analog-style synthesizer to replace my Roland JX-3P on stage. It’s a great synth, but it lacks flexibility and ergonomics for live performance.
I first developed the PolyFM, a similar project based on FM synthesis, which was more easy in terms of CPU usage. My first attempt at building an analog engine were simply too heavy to run on a single Daisy chip.
But after a lot of iteration (and a bit of sweat), I finally achieve to build a solid and efficient analog-style engine with all the features I need : lush pads, aggressive stabs, powerful leads ... I also think I can push the CPU limits with more optimization!
A few years ago, I discovered the Daisy platform by Electrosmith, and it completely blew my mind. As an audio developer, it instantly gave me tons of ideas for synths and audio FX projects.
One of them was to design a polyphonic analog-style synthesizer to replace my Roland JX-3P on stage. It’s a great synth, but it lacks flexibility and ergonomics for live performance.
I first developed the PolyFM, a similar project based on FM synthesis, which was more easy in terms of CPU usage. My first attempt at building an analog engine were simply too heavy to run on a single Daisy chip.
But after a lot of iteration (and a bit of sweat), I finally achieve to build a solid and efficient analog-style engine with all the features I need : lush pads, aggressive stabs, powerful leads ... I also think I can push the CPU limits with more optimization!
Features
- 4-voice polyphony
- MIDI input
- Mono audio output
- 2 VCOs with SuperSaw, Saw, and Square (with pulse width modulation)
- VCO mixing
- -2 to +2 octave range per VCO
- VCO2 includes fifth tuning and fine tuning around center
- Glide
- White noise generator
- ASR envelope
- Low-pass filter with envelope and resonance
- Global high-pass filter
- Master volume
- 2 LFOs with assignable destinations
- 16 presets (save/load), compatible with MIDI Program Change
- OLED display (SSD1306 128×64)
- Mod wheel for vibrato
- Pitch bend (±2 semitones, potentially adjustable in the future)
Component List:
1x Daisy Seed1x H11L1 optocoupler
1x SSD1306 OLED Screen 128x64
1x Jack socket
1x MIDI DIN female
1x 1N4148 diode
4x Push Button (NO)
19x 10kΩ potentiometer
1x CD74HC4067 Multiplexer
1x 220Ω resistor
1x 270Ω resistor
1x 1kΩ resistor
1x 10µF capacitor
1x 100nF capacitor
1x LED
On the electronics side, the design is actually quite simple — everything is handled by the Daisy.
A CD74HC4067 multiplexer is used to manage all the knobs (there are “only” 12 ADC inputs on the Daisy, which wasn’t enough to have all controls directly accessible on a single panel).
There’s also a small MIDI input stage using an H11L1 optocoupler to transmit the MIDI signal to the board. Finally, a status LED indicates incoming MIDI activity.
There’s also a small MIDI input stage using an H11L1 optocoupler to transmit the MIDI signal to the board. Finally, a status LED indicates incoming MIDI activity.
Some features are still in development. If you have any requests or questions, feel free to reach out!
Big thanks to the Electrosmith team for creating such an amazing chip!