I've rolled a lot of tubes with next to no success, from Tung-Sol to black base NOS RCA, EH6SN7 Gold, a few Foton 6H8C's from the 60s, German 6SN7 TAD and after that I stopped because it makes no sense hunting super rare tubes that could break or decide to go microphonic at any time.

All tubes I've tested sound great, but they are all very, very similar to each other in that amp. In fact, they're so similar that any noticeable change could be placebo. Heck even testing things in the evening makes things sound different compared to during the day and that creates some bias towards certain tubes, but in a blind test I most likely couldn't tell them apart.

The TA-26 is absolutely amazing, clean, no buzzing or humming, looks stunning, but tbh, I don't get what many reviews are talking about. There is next to no tube sound, maybe some more dynamics, a little bit more bass, that's it. Even something like the Fosi audio T3 I've tested gave me more distortion. I prefer the TA-26 by a lot, but it's not a game changer when coming from solid state.