A real gem
I've had my TH30 since they came out and have used Tung Sols almost the whole time, but there was always a harsh, unforgiving nature to the high end. I put a couple of Svetlanas in it on a whim and was immediately gobsmacked. Gone is the harshness. Still tons of gain, but with a new warmth to it. The clean channel sounds incredible. Well defined bass and mids, lots of chime. Exactly what my ears have been wanting to hear. IMHO, Svetlanas are the best reissues out there.