Bryan Sims and I are working on a new 3 ply rim I’m calling an “engineered” rim.  We are tap tuning the plys before we bend them into a rim.  With the help of Dr.Rae, we have measured the forced induced vibration velocity of 35 prewar banjo rims. We then measure the new rim with tuned plys and compare it to our prewar data. As you can imagine, there are many  species of maple as well as many densities. We have collected the data from over 40 test rims so far but we are still in the early stages of development.  The good news is that this is going to work. I will be able to predict how a rim will sound by what wood I use.  Check back soon for a mp3 sample of  one of the test rims paired with an HR-30 prototype ring (see the post above). 

Steve