Why not try some NOS? American and European tube companies in the older days of audio made great vacuum tubes. Sylvania, RCA, GE, Mullard, Raytheon and many others...
Preamp tube
Looking for suggestions. I’m considering changing the 12AX7 preamp tubes in my Jolida 1000. Right now I’m using Genalex Hold Lion 12AX7/ECC83. Any suggestions and sonic benefits. Thank you in advance.