In the beginning before there were classical orchestras, chamber quartets, jazz combos or rock n roll bands, there was only one instrument: the human voice. Today, an a cappella quartet from the Twin Cities region, called Tonic Sol-fa, is determined to take this most traditional of all musical expressions and make it the next big thing. In their ten years together, Tonic Sol-fa has established itself not only as the most in-demand vocal group in the Midwest, but also as one of the most successful independent acts in America.