Thanks.
I have others from 4 different kind of tube amps around....
Even my DAC and PA have tubes in it.
Well, start shopping for 6SL7....any recommended brands....
Tung Sol, Linlai, WE, RCA, Mullard?
For American made, Tung-Sol, RCA, Ken-Rad, National Union, Sylvania are all great brands. The smoked RCAs are a solid affordable option. I'm personally interested in a pair of early JAN Sylvanias, somewhere in the middle in terms of cost. Tung-Sol 6SU7GTY and RCA 5691 are some of the most expensive, but they do sound great.
For UK made, Mullard (ECC35) and Brimar (CV1985) are great, but they are expensive.
If you really hate your wallet, you can try to find a pair of Italian Fivre 6SL7. The prices are outrageous.