Tubes and vibration - Atma-sphere MA-1

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I wonder, have anyone experimented with tube damping with Atma amps, especially, the MA monoblocs?

I am concerned that small errors due to vibration (e g airborne vibration) in each of the output tubes, times 14 output tubes per channel, amount to distortion. I have a small OTL desktop amp with one driver and one output tube only, sounding amazingly clear (Audiotailor Jade). In my MA-1 amps, the driver tubes sit very tight, but the output tubes are loosely fastened and rattle easily.

To test, I made two wire rectangles from clothes hangers, and fastened them to the top of the output tubes with small balls of blutac, damping the structure a bit more with balls in between the tubes.

Results - only first impression so far, but yes, perhaps some benefits. More coherence? I will keep them for more testing. In my notes: drums and cymbals are better separated, better treble, bass also? Perhaps some darkening of sound and detrimental effects...

Special tube damping is part of some recent costly designs (like the Einstein The Tube mk2, said to sound better than mk1 because of it). But if cheap tweaks work, why not?

Perhaps other tube amp owners have tried similar things?
Note, I have tried ordinary tube dampers, like Herbie's on some of the output tubes, without much difference (have not tried on all 28 tubes though). If the socket sits loosely, damping a bit from above may be a better idea.
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