I just wanted to report that my P/P UL 4X EL34s, had Svetlana Output valves.
I was curious, so I purchased 4 matched Valve Art EL-34s, that were cryo
treated. The difference was an order of magnitude improvement in all
listening criteria. Of course it was with my and the wife's ears. We do have
many years of listening experience. I don't know if it was the Valve Arts,
the cryo treatment, or both. Just my $.02.
Cordially,
west