I have used these plates with my Theo Wanne Durga 3 and Ambika 2 both 7*, and I use the the heavy copper pressure plates on both. Experimenting with the pressure plate set and reed/ligature position/pressure plate material is really interesting and gives great results as for adjusting and obtaining the sound Your are after. I was very skeptical at first, but when I tried them out, I was fully convinced, there are very noticeable sound differences of the different plate materials. I wanted to soften the sound, and initially went for the vintified plate, since I wanted to preserve the overtones, but it turned out, that the heavy copper plates worked best for me in a combination with Select Jazz filed reeds. The Theo Wanne after sales support is second to none, and a valuable addition to Your purchase. They pay great attention to their customers, which is very reassuring.