Showing posts with label ESP32. Show all posts
Showing posts with label ESP32. Show all posts

Wednesday, April 17, 2024


video upload by zcarlos zc

"ESP32 drum synth Lofi machine.
Sound demo of my DIY drum (or noise) machine.

- Lolin S2 Mini (ESP32 S2)
- PCM5102A I2s dac
- 24 push buttons (8x3)
- Rotary encoder
- OLED display I2c
- 32 LED WS2812B

Synth engine:
- Wavetable synthesizer based on DZL Arduino library "The Synth" (
- 16 sound polyphony
- Sound parameters: Table, Length, Envelope, Pitch, Modulation, + Volume, Pan and Filter.
* Filter (LowPassFilter) comes from Mozzy library (

16 step/pattern editor and random generators (pattern, sound parameters and notes)

Soon schematics and code."



video upload by zcarlos zc 5 years ago in 2019

2 MPR121 modules (24 keys)
4 potentiometer (i2c ADC ADS1115)
RGB neopixel style leds

More info:"


video upload by zcarlos zc also 5 years ago in 2019

2X MPR121 modules
1 MAX7219 module
24 Green/Red LEDS

More info:

Monday, November 21, 2022


video upload by GlakGlikGluk

"Sebelumnya saya sudah berbagi skema dan program data tetapi hasil keluaran suara stereo masih terlalu banyak kebisingan dari tampilan oled dan catu daya, sekarang saya mengubahnya ke tampilan Hi-fi dengan keluaran mono itu terdengar lebih baik. Jika kalian ingin membuatnya saya sudah menyiapkan data dan skema baru di google drive saya .
Link data dan skema :
Modul ini di buat dengan micro controller ESP32 dengan keluaran suara PWM mode Hi-fi tanpa penguat operasional saya rasa sudah cukup
Gunakan catu daya 5V / 1Amper di pin Vin jika inging menggunakan adaptor jika port micro usb cukup charger smartphone saja"


"Earlier I shared the schematic and data program but the stereo sound output is still too much noise from the OLED display and the power supply, now I changed it to a Hi-fi display with mono output it sounds better. If you want to make it I have prepared the data and new schematic in my google drive .
Data link and schematic : .
This module is made with an ESP32 micro controller with a Hi-fi mode PWM sound output without an operational amplifier, I think it's enough
Use a 5V / 1Amper power supply on the Vin pin if you want to use an adapter, if the micro USB port is enough for a smartphone charger.

Wednesday, February 23, 2022

FDSI-8 Digital Synthesizer

video upload by rasool

"This is FDSI-8:

I developed it with ESP32 and some other codecs and components and programmed it with MicroPython."

Untitled video

video upload by rasool

Sunday, February 28, 2021

DIY Synthesizer with ESP32 (super/hyper saw, aliasing free oscillators)

video by Marcel Licence

"This video shows some impressions of using the ESP32 for a little synthesizer project.
All processing is done on one core with sampling rate of 48kHz.
I've connected a master keyboard via MIDI to a serial input.
The synth actually can play 6 voices together (also with 6 oscillators per voice in unison/detuned mode).
The oscillators are aliasing free (wave forms had been generated in advance to avoid fold back of frequencies above nyquist).
Rough ADSR for velocity and filter is implemented.
I am preparing a little arduino project for sharing. It will be available soon..."

You can find additional posts featuring the ESP32 here.

Tuesday, December 29, 2020

WVR : modern, open source, embedded audio for $25

Currently on Kickstarter here.

Quick details via WVR:

"WVR is an ESP32 with a nice DAC and 8GB of fast eMMC memory. 18 stereo voices of simultaneous playback (at CD quality), which I think is something really needed in this space, in an open source project, at this price point.

The project also includes
a USB MIDI HOST add-on board,
a neat JavaScript library called RC.JS designed to help Arduino folks build GUI's, using React Native and Expo
the ability to store multiple firmware binaries in the eMMC, with the ability to boot from any of them
some tools to make building multi-sampled instruments a snap
2 dev boards
a stompbox version
etc, etc."

via the Kickstarter campaign:

"WVR is an open-source embedded solution for audio, with surprising capabilities. It includes everything you need to get started with embedded audio, with no soldering, and no coding necessary. WVR arrives ready to operate.

WVR is also a highly versatile device, capable of powering a new generation of embedded audio design, thanks in part to its wifi and bluetooth radio, providing all the power of a versatile and extensible Graphical User Interface ( GUI ), without the need for a screen or other interface. Users can upload samples, manage firmware, set configurations, build sequences, or control any other data imaginable, both wirelessly, and intuitively, using their laptop, or mobile device, inside a web browser, or even on a native mobile app on Android or iOS.


Playback up to 18 stereo wav files simultaneously, with ~1ms latency

Accepts virtually every audio file format, at any resolution, and any size, including wav, mp3, ogg, acc, flac, pcm, aiff, and many more

Upload audio, map samples to MIDI notes, configure pin functionality, apply FX, manage files, etc, all over WIFI, with the default firmware that WVR ships with, and without writing any code

Holds over 12 hours (8 GB) of stereo audio, at 16bit 44.1kHz resolution

Can buffer over 1.5 minutes (16 MB) of stereo audio in RAM alone, at 16bit 44.1kHz resolution
Optically isolated MIDI input, provides to-spec MIDI input implementation without any additional circuitry

14 GPIO pins, 8 of which can be analog inputs, and 4 of which can be capacitive touch inputs, plus the many peripherals available on the ESP32 .

WVR's Wifi can function either as a Station or Access Point (it can login to an existing wifi network, or can create its own network and accept connections directly from devices in range, without a router or local network of any kind)

write firmware in Arduino, and upload over wifi. Stores multiple firmwares onboard, selectable via the UI. Fully compatible with the extensive, and battle-tested ESP Arduino library, and the exceptionally powerful ESP-IDF framework.

use RC.js JavaScript framework to modify, or custom build, the User Interface that WVR serves to users, without prior knowledge of CSS, HTML, Babel, Node, etc. Even build and deploy native mobile apps for iOS or Android from the same code base. You can play with RC.js in this REPL, try modifying the existing code, to see how it's intuitive, and highly portable, component-based syntax works, and check out the file to learn more.

onboard Ultra Low Power (ULP) co-processor means WVR consumes only ~10uA in sleep mode

Thursday, May 28, 2020

QUN synthesizer: PWM for SAW wave and Triangle

Published on May 28, 2020 Nunomo LLC

Follow-up to this post.

"The synth has a kind of unique PWM for SAW and TRIANGLE.
The product will be available soon."

Additional details via Nunomo:

"Based on ESP32 Lyrat development board, QUN synthesizer is one of the most powerful / versatile full-featured pocket sized synthesizer, with amazing pricing.

Connectivity: Standard MIDI(TRS A type), BLE MIDI, UART MIDI(Supports MAC OS X and Windows through my SerialMIDI.

ESP32 Lyrat

Originally designed for smart speaker.

Analog Modeling engine

The analog modeling engine is made from scratch.

Tuesday, December 31, 2019

open e-drums - Open Source Drum Synthesizer with Teensy 3.2

Published on Dec 31, 2019 Ryo Kosaka


Single piezo pad, Dual Piezo pad, 2 zone cymbal, 3 zone cymbal
Compatible with YAMAHA's 3 zone cymbal(PCY135/PCY155)
Compatible with SoftPot, FSR and Optical(TCRT5000) type hi-hat controllers
Sensing with MUX(4051 and 4067)
Setting mode with LCD or OLED
Sensitivity, Threshold, Scan Time, Mask Time, Note Number can be set with each pad
Works with ESP32 and Teensy and AVR boards such as UNO and MEGA.

"open e-drums" is a completely open source electronic drum. Pads that can be produced with 3D printers, and midi converters are all open source hardware. Arduino code for sensing is also available. You can create your own e-drum from scratch, or add pads to the Roland and YAMAHA kits.

This project started by accident. At the time, I was a product design student who had used Arduino just a little. When I found a drum mania controller at a used store at a bargain price, I was somehow attracted to it and bought it. This is the beginning of everything. I took it apart and played with Arduino. I used a piezo for the first time at that time. I learned the delicate sensing ability of piezo. I realized the greatness of electronic drums such as Roland, Yamaha, and Alesis, which process the signals beautifully. I want to try it myself.

I didn't have any knowledge of programming or electronics. In other words, I have acquired a lot of knowledge through this project. For some people, this project is just a reinvention of the wheel. But it's a very meaningful project for me. As I proceeded with this project, I drew on the knowledge of many predecessors. Many of them keep information open. That's great. So I decided to publish this project as an open source hardware project. I would be happy if this project helps someone create something."

Monday, April 01, 2019

Gecho v2 Prototype and Korg Volca FM

Published on Apr 1, 2019 Gecho Loopsynth

"The v2 prototype is working very well so far, here the MIDI Out functionality is being tested with Korg Volca, also Line-in and Line-out connectors are actively used. All is recorded via USB sound card directly from Gecho and presented in raw form. You can find more info here:"

"The final Gecho v2 prototype
Since the previous update about v2 that was posted in August last year, it took 3 more revisions to get here. Although the first prototype of Gecho v2 has been completed, blueprints verified by our skilled hobbyists friends who soldered their own prototypes, and it even passed CE/FCC testing with flying colours, and we could go ahead with the production - it was just not good enough - it needed a small upgrade. And, things tend to turn more complicated than they appear :)

Thanks to everyone for encouraging comments, questions and feedback during the past few months, it has been very helpful and contributed a lot to shaping the new model.

While working on Glo (the whale synth), I came to realize that sticking to STM32 platform looks nice in short-term; in theory, only small modifications are needed to port the firmware over. But there was a risk that when implementing the new features you are waiting for, like MIDI and sync modes, it would be needed to trade off something on the sound side (e.g. level of polyphony) to get the extra power for the additional processing required.


Patch n Tweak
Switched On Make Synthesizer Evolution Vintage Synthesizers Creating Sound Fundlementals of Synthesizer Programming Kraftwerk

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