Some guitars sound better with different strings too, IMO. You've got bronzes, brasses, phosphors, sink & steels, coated strings, etc. You should try `em all and see which sound you prefer on each machine. Best if you do it infront of a flat wall so you can get the sound reflected back to you, but you also have to like the sound you hear when you don't get the reflection too, since that's how you'll most often hear it.