KoshNaranek
Headphoneus Supremus
I have come to the conclusion that audio is very subjective and it difficult for one person to unreservedly recommend equipment to another.I rarely listen to solid state amps even though I own several, all are class A.
I sent some tubes for a Mjolnir to @KoshNaranek, Amperex and Reflektor as best I recall maybe he can jump in and help? I have given away most of the spares I rarely listen to or I would help out more.
I am terrible at describing tube sound and the point system I use would be meaningless to most folks, I tend to use Reflektor silver shield 6n23P's from the mid seventies, someone like @bcowen could certainly help with other tubes that might be less costly.
For some reason, tubes appear to be even more subjective than most audio equipment. For example, I agree with @Ableza recommendions on speakers and headphones. I disagree with his recommendations on tubes for Mjolnir. (Gold Lion)
@bcowen hates GE but my wife and I don't think that they are that bad
My wife hates RCA tubes in Freya but I like them. Both of us Like Hitachi and we don't like JJ.
She clearly prefers PS Audio Directstream DAC to Yggdrasil while I think that they are pretty close in sound and don't have a strong preference.
With this in mind, I suggest finding a vocal member of this community whose recommendations you agree with on specific items that you, yourself have tried and extrapolate from there.
In the end, please remember that free advice is frequently worth exactly what you paid for it.