Why some preamps does not play music? Cold?


I mean technically/electronically wise, why some preamps while been very revealing and very good in reproduction of frequencies and extensions, are at the same time not engaging musically and emotionally and even boring? Are there a solutions to fix that (except for changing preamp)?
dvavc
knghifi: "It’s very possible ... GZ34 family?" Yep. Russian. You really believe it might cause the problem at issue?
as a matter of fact, those Sylvania which i have currently installed are extremely microphonic. Are you suggesting it might cause the issue i'm talking about? 
Microphonics can cause brightness and amusicality. Any tube used for audio should be hand-picked for low microphonics.
Dvavc,
I think you may be getting closer to the "possible" cause of your complaint thanks to Atmasphere, Bombaywalla and Knghifi. Your response to georgelofi was appropriate given your original quest. and stated objective. Good Luck.
Charles,

Surprised he wasn't told just buy a voodoo fuse, which fixes problems.


Cheers George