DIY synthesizer soundengine (using ESP32 Arduino) - Little demo of the Roland Alpha Juno like sound

video upload by Marcel Licence

"This video is only a short sound demo of a little sound engine I tried to implement.
I recommend using a stereo output (phones or speaker) for the best listening experience.
It is based on the Roland Alpha Juno synthesis but slightly modified.
The sound is some kind of pulse width modulated saw wave without chorus.
A LFO drives the pulse width for both channels independently creating the stereo effect."

Projects can be found on GitHub: https://github.com/marcel-licence

Additional demos:

ESP32 DIY polyphonic MIDI synthesizer module for Arduino


ESP-8266 stepper motor midi music module (ESP32 "synthesizer" Arduino project)


My first PCB for arduino based synthesizer projects - a quick look at the HW for ESP32/DaisySeed


"I started to design my first PCB which I just want to show in this video.
I would like to take a look at some of the designed features.
It is more a little presentation and demo and does not include details of how I made it.
The background is that I wanted to have a multipurpose platform and avoid wiring.
In addition to that I wanted to be more independent from existing hardware (like the ESP32 Audio Kit).

Some details of the PCB:
- it can use the ESP32 WROVER-E or the Daisy Seed as main processor
- can be directly connected to the Audio Kit and be used without a processor attached
- MIDI in/out sockets (input optocoupler circuit)
- audio in/out sockets (for using the Daisy Seed)
- SD Card (full SD/MMC support - no SPI)
- USB / UART (CH340) for a serial interface and also programming the ESP32
- ADC multiplexer (for 16 analog inputs used with only one ADC pin of the ESP32)
- GPIO multiplexer (for 24 additional GPIOs + 8 for internal use)
- 2 SPI headers (for SPI components and/or displays - multiplexed used with only one SPI port)
- WS2812 connector (especially to connect WS2812 LEDs/LED strips)
- place to hook up a PCM5201A breakout board for audio out
- power management - 3V and 5V when attaching for example 9V external supply"