SendspinZero is an open-source, DIY Sendspin audio receiver for your amplifier that relies on off-the-shelf parts costing around $10 and a 3D printed enclosure. It integrates with Home Assistant for multi-room audio synchronization.
It sounds good, but what is Sendspin exactly? It’s a royalty-free, open protocol developed by the Open Home Foundation for synchronized audio playback across multiple devices and rooms. Besides audio, it also supports screens for album art and control music, and sound-activated lights (coming soon feature). The protocol enables open-source products that compete against proprietary systems like Sonos, AirPlay, or Google Cast, and integrates nicely with the Music Assistant add-on for Home Assistant.
Sendspin audio receiver key components:
- Waveshare ESP32-S3-Zero board with 2MB PSRAM (About $4-$6 on AliExpress, $12 on Amazon), ideally the version without pre-soldered headers
- Optional 1.54-inch LCD screen (About $5 on AliExpress)
- Optional 3-6V, 22mm bi-color button (About $2 to $3)
- Audio output options:
- 3.5mm audio jack using PCM5102A DAC board ($1-$2 on AliExpress)
- Optional optical (A1) or coax S/PDIF (RCA) connector (the PCM5102A board is not used)
- A few wires…
Prices are approximate since I’m shown “welcome deals” for $0.99 for most items. The total for the display + 3.5mm audio jack module should be a little over $10 before taxes and shipping, unless you get discounts.
You can build nine different variants with three audio output options (Coax S/PDIF, Analog Stereo, optional S/PDIF) and no display, a 1.54-inch display, or a bicolor button.
You’ll also need a 3D printer for the case, and a soldering iron to solder the wires in a way that fits inside the enclosure. It doesn’t seem too complicated to reproduce, and you could also test it with a breadboard.
The ESP32-S3 board simply needs to run ESPHome with YAML configuration files for all nine versions and 3D files for the enclosures available on GitHub, along with detailed instructions. If you scroll down, you’ll also find other variants, including a 1.9-inch display + bi-color button model, which looks pretty neat.
There’s no information about the Home Assistant + Music Assistant integration part on GitHub, and for that, you may want to check the official documentation.
Thanks to Hedda for the tip.
Jean-Luc started CNX Software in 2010 as a part-time endeavor, before quitting his job as a software engineering manager, and starting to write daily news, and reviews full time later in 2011.
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Title should probably also mention Music Assistent since Sendspin is at this time primarily made for Music Assistent and was even founded by the founder of Music Assistent, even is Home Assistant is now beginning to migrate its audio output and input pipelines to Music Assistent and Sendspin.
I found the title a bit too long with Music Assistant.
You can do the same with squeezebox on esp32 since ten years (and from my test, it was more reliable):
https://github.com/sle118/squeezelite-esp32
Yes but even if it is the Sendspin specification still experimental it is new official audio experience protocol from the Open Home Foundation for Music Assistant and Home Assistant. So while you could say that Open Home Foundation follows its fundamental principles of privacy, choice, and sustainability by supporting all other protocols for cross-ecosystem interoperability or legacy compatibility, Sendspin is the only protocol that the Open Home Foundation will actually promote and will activley work to improve and extend.
Unfortunately, the chip antennas of the S3 zero and similar mini boards are crap.
Respectively, the layout is far from the recommendation in the datasheet of the antenna, and therefore the performance is really bad.
Unless you plan to place the thing close to the WiFi router, better use a board with a classic PCB antenna/proper layout/external antenna.
Which reminds me of the antenna hack @ https://www.cnx-software.com/2025/04/09/antenna-hack-more-than-doubles-the-range-of-cheap-esp32-c3-usb-c-boards/
That’s for the ESP32-C3 instead of the ESP32-S3 board, but it should be the same.
Or maybe the project could switch to the XIAO ESP32-S3 board for a few dollars more, and minor modifications to the enclosure.
I recently bought two ESP32 C6 mini boards with this antenna and can confirm that the WiFi sensitivity is really bad. Even 6m to the router do not always work. It’s probably not only the antenna but as well the board design (as you mention).