Do tube dampers improve sound?

I have found that the very heavy brass tube dampers that Andy Bouwman of Vintage Tube Services sells make an audible and positive difference in the EF 86 tubes in my preamplifier, better focus of images being the primary benefit.

Tube dampers are primarily used to prevent or minimize microphonics in small signal tubes such as 6922's. I would not go overboard here and spend alot of money.

All I can say is, try it for yourself and see. I have used them on and off in my equipment, and there were occasions where I thought they made a nice improvement in focus and clarity on some tubes, but on other equipment it took the "life" out of the system. The dampers will be tube and equipment dependant.

I use the Herbies Audio Labs Hal-o dampers on the 6922 tubes in my ARC LS-15. They did make a difference. They cleared up the soundstage a little and separated things a little better, but don't expect night and day difference with 6922 tubes that are low noise and low microphony, such as carefully selected and properly matched set of EH6922 tubes for example. WHats good about Herbies, is they come off easily and the never stick to the tubes due to heat.
http://herbiesaudiolab.home.att.net/

I used Halos on my Tenor 75OTL's. The Halos made the single biggest sonic improvement I've ever heard in my system. It's astonishing how much distortion I believed was in the music was eliminated and enhanced clarity, detail and lower noise floor I got.

It was shocking. Now how do I fit tubes into those DarTZeel's?

Then I could improve it with Halo's...