I use a couple of the old brass ring/sleeve style tube "coolers" from Vintage Tube Services. The real value to me is the same that Delof gets. The microphonics are reduced considerably because they are very heavey they dampen vibrations well.
It has been argued that these older tube tweaks actually keep the heat in. In theory if you run a tube at a higher temperature than it is engineered for the filament lifespan is shortened. I roll tubes a bit so I can't say if they shorten the lifespan or not.
The tubes do not seem to get notably hotter either. The ring does dissapate some heat which may in fact, result in a cooler tube. You get vibration dampening as wellof this I have no doubt at all.
Since these are gold plated and/or highly polished they look really good- so why not. BTW Brente Jesse at audiotubes.com sells or sold a very similar product. I think VTS is no longer selling them.
It has been argued that these older tube tweaks actually keep the heat in. In theory if you run a tube at a higher temperature than it is engineered for the filament lifespan is shortened. I roll tubes a bit so I can't say if they shorten the lifespan or not.
The tubes do not seem to get notably hotter either. The ring does dissapate some heat which may in fact, result in a cooler tube. You get vibration dampening as wellof this I have no doubt at all.
Since these are gold plated and/or highly polished they look really good- so why not. BTW Brente Jesse at audiotubes.com sells or sold a very similar product. I think VTS is no longer selling them.