So far, ESP boards have been known primarily for their network capabilities. But the two-core chips of the ESP32 are also well suited for processing images and sound in terms of performance. After the introduction of the ESP32 camera, more and more inexpensive boards for sound processing are coming onto the market.
The ESP32 LyraT board from Espressif in the latest version 4.3 offers a lot of additional hardware in addition to an ESP32 on the board, for example an audio codec of the type ESP 8388. Each contains a 2-channel AD and DA converter, Microphone and headphone amplifier, sound effects and mixer functions. It communicates with the ESP32 via I.2C- and I2S buses.
In addition, there are two audio amplifiers on the board for controlling 4Ω speakers. The connection is made via Dupont connector strips. 3.5 mm jack sockets are available for headphones and as a line-in connection. There are also two microphones on the board.
The functions such as recording, playback and the like can be controlled with four touch fields and four normal buttons. The programming is done via a micro USB socket. A second USB socket is used exclusively to power the module or to charge a battery connected to the module.
On Github there is the official audio development frameworkwhich, in addition to the software, also contains extensive documentation for the module. The manufacturer Espressif also provides one documentation ready, which among other things reveals the internal contact assignment of the board.
The board is currently being offered at AliExpress for 15 euros including shipping.