Octal K8A 8-Pin tube-valve-base
good for guitar amps (Marshall sound), good mids, nice harmon...

This is the nowadays Gold Standard 12AX7-ECC83-7025 tube
...

EL12N Powertube with 12-pin steelsocket Y8A- it is made in Germany.
It is very similar to EL...

Noval (No15) B9A 9-Pin tube-valve-base-Röhrensockel
warm, tight, sound - good for Blues, Jaz...

Octal K8A 8-Pin tube-valve-base
The perfect 6SN7GT-VT-231-5692-6180 for Audio and Studio Appl...

Noval B9A 9-Pin tube valve base Röhrensockel
Gold Standard EL84 for Audio, Guitar, Radio, Re...

Octal K8A 8-Pin base
the best price rate for Musical Amps like Ampeg SVT
height:101mm-...

The GZ34s from JJ ist a very reliable replacement for your tube amp.
it is a 100% equivalent...

Noval B9A 9-Pin tube-valve-base-Röhrensockel
usable for tube Audio and UKW, HF Applications ...