Hello PCBWay community, this is Dario. I am an Italian electronics engineer, with huge passion for audio and music.

I'm happy to share with you a nice project: BassFly uHAT. It is an expansion board for Raspberry Pi Zero, but it will work fine with other Rasbperry Pi versions (2, 3A, 3B, 4) and with ASUS ThinkerBoard too. It's been designed following the mechanical specification for uHAT form factor.

Together with Volumio ( https://volumio.org/ ) it will turn your Raspberry Pi into a tiny but powerful digital radio.

BassFly uHAT is powered by the following peripherals:

• 2x TFA9879/TFA8200 amplifier from NXP. They have an embedded DSP for HW volume control, HW 5-band equalizer and HW dynamic range compressor; they can deliver up to 2.5W RMS output power each (with 4Ohm load)
• 4x Tactile button, for playback control (play/pause, prev/next, vol-up/vol-down) or for safe shutdown
• 1x RGB LED, for SD-card activity or for playback status indicator
• 1x 0.96" I2C OLED DISPLAY MODULE 128X64 SSD1306 (optional), to display an information screen including a music frequency spectrum ( https://github.com/antiprism/mpd_oled )
• 2x INMP441 MEMS Omnidirectional Microphone module (optional), not necessary for Volumio at the moment, but they can be used for other projects (Google-assistant, Alexa-assistant, voice-triggered in general)

Full documentation is available on public Github repository, including BOM and SMD positioning files, for automated assembly.

https://github.com/Darmur/bassfly-uhat

Please feel free to download gerber file and documentation, to order PCBs and to copy/improve it, if you like!

regards

Dario