Fiddler,
Are you sure you have round plates and not just tung sol 6sn7's? My tung sol round plates sound fantastic from top to bottom. Smooth in the top end, great midrange and solid, deep bass. Mine sounded this way from the day I got them. BWhite once posted pictures of the Tung Sol round plates on this thread, but I doubt if I could find it. I will try. If I do, I will let you know where to find them. Guess I need to get a pair of the EH6sn7's to see how they stack up.