There are several great audio boards on the market that make use of the popular ESP32 SoC, such as Seeed’s Ai Thinker A1S Wi-Fi+BT Audio Development Kit, Lilygo’s TTGO TAudio, and Espressif’s ESP32-LyraTD-MSC. We can now add Olimex’s ESP32-ADF audio development board to that list, and like all the boards listed above, it also uses Espressif’s Audio Development Framework. The framework enables users to build any number of audio projects — including an Alexa speaker, Internet radio receiver/streaming device, SIP VoIP phone, Wi-Fi-based walkie talkies, and more.
Under the hood, the ESP32-ADF sports an ESP32-WROVER-B module, with 8Mb PSRAM and 4Mb of Flash storage. It packs a pair of microphones, stereo speakers with amplifier (2X3W), 3.5mm audio output jack, micro USB port (power/programming), and onboard charger and LiPo battery header. Rounding out the features are a UEXT connector for an optional 2.8-inch LCD, IR receiver, four touch buttons, three tactile buttons, and a power jack.
Olimex has uploaded the KiCAD schematics, Gerber files, PCB layout, and BoM to their GitHub repo, and will eventually supply the code necessary for creating an Internet radio player, Alexa speaker, and VoIP telephone sometime in the coming weeks. The company mentions that the open source hardware carries a CERN OHL v1.2 license, while the software will be under a GPL3 license and documentation under the CC BY-SA 4.0 license.
There is currently no documentation or any information on what software it supports at this point, and it’s unknown if that information will be listed in the coming weeks. The ESP32-ADF audio development board is available for about $24.46 on Olimex’s product page.