Boy, this was a tough question! It was nowhere to be found in enotes, but I did find an answer on the internet, whether it is THE answer I don't know. I did learn a lot about violins, fiddles and "Cold Mountain", however. Brendan Gleason actually plays the fiddle, for example. The article I found was "Three "Classical" Violins and a Fiddle", and the suggestion I got from this was that the type of fiddle played in "Cold Mountain" was called a Norwegian Hardanger Fiddle. It possesses a short neck with comparably short strings and a relatively flat bridge, the hardingfele. The Norwegian Hardanger Fiddle produces a powerful and mesmerizing sound and can actually procuce a sound that can ring like a bell. Once again, I'm not sure if this is exactly what you needed, but this was a tough one!