I would love to try something different like a crystal over crystal in a walnut pot.I know that the majority of crystal doesn't come in sound board size but could it be ground to fit or does it have to be perfectly round to work as a sound board and fit in the pot? If any call makers feel they can pull it off I would be willing to buy it. Just get a hold of me on here either p.m. or open forum. I feel it would be similar to glass over glass but you never know . Thanks