I recently rolled in a number of different NOS tubes to compare to the stock EH's that came in my amp and the stock Sovtek's that came in my preamp. The tubes include NOS Amperex PQ's, NOS Silvania Gold Brand, NOS Telefunken Smooth and Ribbed plates, NOS RCA Clear tops and the now unobtanium NOS 1963 GE long plates. While there are considerable differences between these tubes as to SQ, all of them sound to my ears superior in one way or another over the EH's, or the Sovtek's. YMMV.
Telefunken vacuum tube E88CC-TK; NOS versus brand new.
Telefunken vacuum tube E88CC-TK; I just purchased a pair of these and they are fantastic; they raised my phono to a new level.
Now here's the question, I paid $60 apiece for a pair of these brand new. "Uncle Kevin" at Upscale Audio, sells these for $349. apiece. His are NOS, they should cost more, they also probably last longer, but do they sound better? That is the question. It is not in my budget to pay $700. to find out. Do you have any comments on this?