Expanding questions about tubes in a preamp

If a tube is microphonic simply replace it as dampers won't save it and are basically useless (and look silly)...note how many great tube amp designers don't bother with dampers...Shindo, Dennis Had, VTL, VAC, etc...they didn't get the memo? The myth that "all tubes are microphonic" is ridiculous and isolating everything is impossible and unnecessary...just listen to your amp and relax.

Did you learn that in audio school, wolf boy? 😳

Hi,
looks silly or not if it works it's ok. If my memory is correct ARC did supply tube rings sometime with their gear. Virtually all tubes have the tendency to be microphonic (more the signal tubes) but it does not mean that they are bad ones. Most depends in their location on the circuit, a gain stage will expose it more and a driver stage less, so sometimes you do not even know it. Have you tested that all the tubes you are using are not microphonic and how? What sound do they make when you tap them?
Everything works, and my comment on a previous post that they sound more linear after using a tube damper is because microphonics/micro vibrations are somehow reduced. Last about hissing, we are talking about tubes which obviously have more hiss than ss.

A  with tube damper testing is it is impossible to install / adjust them without moving the tube and refreshing contacts.

Dampers could work by two methods: Vibration control and resonance damping. Assuming the envelope vibrates, what happens? The tube is a vacuum and sound does not travel in a vacuum. It could damp sound, which has very little energy, from travelling down the envelope to the base and up into the electrodes. One should be able to mathematically calculate the energy required to vibrate the electrodes. If resonance damping is the m.o. then where the damper is placed will affect its utility. Since all tubes vary slightly, how does one know if the location is correct for the particular tube. Model or item. AT, AU,  AX, AY, BH // 66, 77, 88, 90, 120 150 for but two families.

It is quite trivial to set up a test wherein one records the output of a tube device w/wo dampers and delta the difference.

Since damper claims are anecdotal, I assume it's never been proven.

ieales

Sound improved greatly adding the preamp in: better defined bass, voice
/ vocals more clear and moved "vertically up" in soundstage; veil over sound lifted slightly; soundstage expanded in width and depth with most instruments more clearly defined in the soundstage, rhythm and ’ toe-tappin ’ factor greatly enhanced...

Today’s Music: Dixie Chicks, Grateful Dead (especially Franklin’s Tower, on repeat), June Christy " Something Cool (both mono and stereo), Best of Blondie and Best of Van Morrison...