I cannot get back into tubes myself at all. I grew up on tubes and have used many tube high power transmitters and receivers over the years. Love em; but they are in my opinion too noisy and subject to degradation due to poor vacuum or internal break down. In other words, variations in specifications ; it’s 100 year old technology. In fact a few years ago I had the US importer and distributor of a very high end amateur radio/military linear amplifier over to my place in order to swap out the final output tube pair in the amp. We went through at least a dozen pairs of NOS 4CX800 ceramic tetrode tubes before we were able to match two which were close in specification. Nope, not for my audio gear. High power transmitters with lower spec audio requirements are fine, but in my audio gear I am more interested in the latest technology.