Actually if my memory is correct it does not matter. When I was studying acoustics of wind instruments to better understand how I want to make my trumpets its not the curve of the tube but transitions, tapers, length, diameter, and internal resistance that make the biggest difference.
Look at trumpets, tubas, etc. They are all curved and if I remember my reading they would sound the same uncoiled just a lot harder to march with.
If it sounds good I would not worry one bit. Sometimes mistakes are what creates the next best thing.
