This is an idea I stumbled on while I was trying to do something else. It is a bridge or river harp and is similar to a windharp except that the current vibrates the strings instead of the wind. The resulting sounds vary depending on the length and gauge of string used, the speed of the current and where in the river you hang them. My favorite thing about these is that as algea builds up on the strings they grow quieter and eventually stop singing altogether. You also get an occasional leaf or other debris banging into the strings which add sudden sounds to the drones. This particular recording was made with 2 different gauge strings in slower water so the sounds are quite low. Enjoy.