bcowen
Headphoneus Supremus
Lots of money being spent on tubes for a Vali2. Try a couple cheap tubes like the GE 5670W with an adapter for $10-15 and call it a day. It's a fantastic amp and I love mine but don't go overboard. That tube has great mids and decent airy treble, much better than the stock tube and quite affordable.
Of *any* tube I'd recommend for the Vali 2 a GE 5670 would NOT be it. Sorry. Beyond the fact it was one of the few tubes that was actually made by GE, it's one of the worst sounding 2C51 / 5670 / 396A variants around. Try a Sylvania, WE, Tung-Sol, Tesla...any of them make the GE 5670W sound like fingernails on a chalkboard.