Good question. The final decision was made lounging at a local coffee shop, after whittling down three pages of scribbles to a few possibilities.
We looked through everything for a few weeks until I came up with the word "signal": dictionaries, thesauruses, Biblical concordances, advice from OCR folks, random band name generators.
When I first started looking, I was thinking something much more abstract of a word--even to the point of creating a new word by meshing different ideas together. Then I came across "signal" and thought it was perfect for an electronic artist. The "sole" creates a double meaning; it's a play on both Christian themes and the more obvious connotation of it being "the" music to listen to.
The soul/sole thing is the only thing that could cause minor confusion but I like the "a-ha!" moments that it creates (just like Neko mentioned), and it's also worth it for the meaning behind it.
Still haven't decided if I want "sole signal" or "Sole Signal" here at OCR.