This breakout board is the ultimate companion for the VLSI VS1053B DSP codec chip. The VS1053 can decode a wide variety of audio formats such as MP3, AAC, Ogg Vorbis, WMA, MIDI, FLAC, WAV (PCM and ADPCM). It can also be used to record audio in both PCM (WAV) and compressed Ogg Vorbis. You can adjust bass, treble, and volume digitally. There are also 8 GPIO pins that can be used for lighting up small LEDs or reading buttons. All this functionality is implemented in a light-weight SPI interface so nearly any microcontroller can play audio from an SD card. There's also a special MIDI mode that you can boot the chip into that will read 'classic' 31250Kbaud MIDI data on a UART pin and act like a synth/drum machine with dozens of built-in drum and sample effects! Perfect for use with an Arduino but also good for other microcontrollers that just don't have the computational power to decode MP3s.