This is a nice way to access a TDA7313 Audio processor via an AVR, an LCD screen, and a few simple buttons. The website has all the compiled firmware, WinAVR ready source files, and Eagle files available to download.
The TDA7313 audio processor has been used for more than ten years in the industry because of its simplicity, functionality and good parameters like low distortion, low noise. Chip is based on BIPOLAR/CMOS technology and can be used in various applications including car radios, Hi-FI, simple mixers.
Make your own AVR based TDA7313 Audio processor control