Tubes, to damp or not to damp?

I have had great luck with Herbies Ultrasonic RX rings at $27.00 each.They damp but do not over damp like ARC dampers.

I’ve used Herbies UltraSonic SS dampers without any over damping effects. They prevent acoustic vibration from speakers or resonance from audio racks, especially on components with exposed tubes. Also good for tightening up the bass on some tubes.
The ring type dampers can suppress overtones and harmonics.

I generally don’t use them on tubes enclosed in a component unless a tube has some microphonic issues.

Tried Herbies. Strangles the life sounds about right to me. A much better approach would be to try fO.q tape. Not directly on the tube, they probably get too hot. But on the cover near the tube. Or on the caps inside. Have not tried it in those locations but where it has been tried- tone arm, crossovers, speakers- it works wonders. 

Unlike most vibration control that relies on mass or mechanical damping, fO.q tape uses the piezoelectric effect to convert vibration energy into heat. Very high quality tape with an extremely high quality adhesive it sticks easily and yet can be removed just as easily and without leaving any residue. Impressive stuff. Not cheap, but worth the money for what it does.