I've published the successor for this project based on the Papilio FPGA Papilio-DSPWing
I've been receiving a couple of emails inquiring about this project the past years, and I feel I should have left a few more notes in this readme. The reason to why this project has been pretty much abondoned is because the Arduino doesn't have enough processing-power to accomplish any realtime signal processing. So after finally managing to get this project to just do a plain Audio-passthrough and realize the extremely bad quality and chunkyness of the sound I started looking for alternatives. The raspberry has more juice but also alot more overhead thus, I've never had good results with the highlevel DSP tools like jackd & rackarrack etc.. The Arduino DUE might cut this cheese. But currently I've switched my attention over to the Papilio Pro, it's become a long-term project... I'll let you know once I have anything more for share.
Digital signal processing for the arduino. This is my personal working project based on the original work done by Kyle McDonald http://www.instructables.com/id/Lo-fi-Arduino-Guitar-Pedal/?ALLSTEPS
The circuits I use are almost identical to Kyle's will have to document them later.