$25 Open Source Embedded Audio Player Plays Up To 18 Stereo Samples Simultaneously

Developer Andrew John March has launched a Kickstarter project to fund production of the WVR, an open-source embedded solution for audio that can play up to 18 channels of audio simultaneously.

It includes everything you need to get started with embedded audio, with no soldering, and no coding necessary.

WVR is a versatile device, capable of powering a new generation of embedded audio design, thanks in part to its WiFi and Bluetooth radio, providing 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 needed, wirelessly, using their laptop, or mobile device.


  • 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 README.md file to learn more.
  • Onboard Ultra Low Power (ULP) co-processor means WVR consumes only ~10uA in sleep mode

Pricing and Availability

The WVR is available to project backers for about $25.

Note: All Kickstarter projects can involve risk – see the project for details.

10 thoughts on “$25 Open Source Embedded Audio Player Plays Up To 18 Stereo Samples Simultaneously

  1. Particularly curious about the Physical Modelling claim, especially given the emphasis on sample-based uses.
    Otherwise, it sounds like it might have some advantages over existing boards, such as the fact that it’s ready to play. The campaign video makes it sound like there aren’t other boards out there, making it difficult to back when you already have these other devices.

    At one point, it might make sense for Synthtopia to do a kind of roundup of DIY-focused devices, maybe in partnership with Hackaday?

    1. Ohhhhhh yes! It is literally a digital Mellotron out of the box.

      If you wanted to get fancy and write some code, you could even model the wow/flutter of the tape 🙂

      1. If you’re using it to play samples taken from an actual Mellotron, the wow and flutter and all the other artifacts have already been captured.

  2. Crunchy, I can answer that: it sounds like a window splattered with 8Khz s**t! If you need a ‘tron, M-Tron Pro is $129, with a huge library of both original Streetly and custom sounds. Arturia’s Mellotron V is $199, with only a paltry 61 presets, but it offers user wav drop-in, so its wide open from that angle. $1000 will get you a 2-octave Mellotron Micro @ digitalmellotron dot com. Several good options to consider.

  3. Looks like fun to my DIYer heart. 8 sample triggers with 1 Knob/CV function for each sample sounds possible. 18 single cycle drone, polyphonic wavetables, looper, delay modulation effects, CV MIDI, Audio analysis and and and …. nearly everything an Arduino user dreamed of already … if someones out there interested in sharing some eurorack thoughts, i will dive into this the next weeks. ecolabaudio.de

  4. Wow those Faust libraries are amazing, thank you for pointing that out, I hadn’t seen this before. Yes that would absolutely work for WVR, the only change would be to write the driver for the DAC. I will do that 100%

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