Tube Discussion Microphonics?


I have read in quite a few places where someone complained of this tube or that being microphonic. I understand what is meant in a discussion of matching output parameters but I have heard people say that a pair, or quad, of tubes were matched but still microphonic.

What does it mean for a tube to microphonic? How does this translate into audible identification? I mean how do you tell by listening whether a tube is microphonic or is just not a good sounding tube or not good sounding with a particular component?
motdathird

Showing 1 response by motdathird

I appreciate the responses and I will give my case in point. I recently bought a quad of 60's Telefunken 6922's for my linestage. They tested (16.0, 16.0), (15.5, 16.0), (16.0, 15.5), (15.0, 15.0). I had original Sovteks that sounded dry and did not have very good extension. I tried some Tesla that were so-so as far as extension but the midrange was like back in the next room.

I installed the Teles and the soundstage is great, midrange super, and highs brilliant and detailed (but not edgy). However, the low end, especially mid to low bass is really bloated. I had basically the same Teles in a linestage previously and the bass was very tight and controlled. So, I am wondering if this is a tube component mismatch or if it is a problem with one or more tube(s).

If any of the tubes were microphonic, would I have audible problems throughout the range or could it be frequency-specific?