DIY Tube Dampers

From kee–(at)–ustin.ibm.com Tue Feb 6 11:27:24 CST 1996
From: kee–(at)–ustin.ibm.com ()
Newsgroups: rec.music.makers.builders
Subject: Re: Tube heat
Date: 6 Feb 1996 13:56:16 GMT
Distribution: world
Originator: kee–(at)–een.austin.ibm.com

In article <4f6kgq$o--(at)--ewsbf02.news.aol.com>, jorma–(at)–ol.com (J Orman) writes:

> What I’m looking to do is to find some o-rings that can withstand the heat
> to use as dampers for the tubes… 100 – 130F is no problem if that’s all
> a preamp tube does….I’ve heard of using stretch watch bands as
> damper-coolers for tubes. They could take a lot more heat.

Ah. I see. The watch bands trick will work, or you can go to an auto parts
store and buy some of Perma-Tex’s silicone rubber gasketing goo. This stuff
is like RTV, except it is opaque red and will supposedly withstand up to
about 500F (they say…). This ought to be a good thing to run a bead around
the base of preamp tubes just above the socket line.

O-rings would work, but I wonder if the hard rubber would make for much
mechanical damping.

The Permatex ought to be good for gooping on the socket-to-chassis joint, too.
You could drill the rivets or remove the screws and nuts holding it on, goop
the joint, then put in new, slightly longer screws. This should damp a lot
of chassis borne feedback. I’ve seen a lot of older chasses with rubber
o-rings between socket and chassis.

Some urethanes are fairly high temp, too. A ring of softish urethane would
make a good – and removable – damper.

R.G.