Tubes and microphonics


I want to know when microphonics affect the sound.
I have a Sonic Frontiers Line 2SE Preamplifier. I tried many tubes like Valvo, Siemens, Reflector 6H23NEB.
Recently I bought two matched pair of Amperex 6922PQ White Label Made in USA. I think that the Amperex are better than the others, but I could see that they are less silent.
When I knock the cover of the preamplifier I can hear the knock clearly in the speakers. That not happen with the others tubes. The 6H23NEB are the most silents.
I think that Amperex have more gain than the others. But I don“t know when that is critical to the sound.
Please let me know your experience with your tubes and preamplifiers.
Thanks,
Pablo
elduende14

Showing 1 response by elduende14

Marco,
the Reflector (Russian) 6H23NEB are very good tubes (much better that the standard Sovteks)and they ultra low noise (an excellent tube for Audible Illusions preamplifiers) but the Valvo 6dj8 and the Amperex 6922PQ are really better. Unfortunally I tried the Siemens E88CC but for me the Valvo and the Amperex are better.
You can contact to Mr. Chris Johnson at Partsconnexion. He sell the 6H23NEB at 45u$s(matched pair) and the Valvo 6dj8 at 75u$s (matced pair).
The Amperex PQ are really difficult to find but for me they are the best.
Thanks for all for your answers.