I recently completed an echo/delay effect “pedal” project. Although I originally developed and tested it with an electret microphone and speakers, it can be easily adapted for other input/output such as an electric guitar and amp. I used an mbed to do the actual effect processing, and the code can also be easily adapted for a different effect. See my dev wiki for more info (pictures, schematics, and code), including a video of it operating with an electric guitar: http://dev.frozeneskimo.com/embedded_projects/audio_echo_effect.
Audio Echo Effect “Pedal”
I recently completed an echo/delay effect “pedal” project. Although I originally developed and tested it with an electret microphone and speakers, it can be easily adapted for other input/output such as an electric guitar and amp. I used an mbed to do the actual effect processing, and the code can also be easily adapted for a different effect. See my dev wiki for more info (pictures, schematics, and code), including a video of it operating with an electric guitar: http://dev.frozeneskimo.com/embedded_projects/audio_echo_effect.