[John Casler]

OK just because I was accused of being a "cheapskate" (does anyone know where that term came from?) doesn't mean I am one, but I do like a "Cheap Tweak"  every once-in-awhile.

So here is one to try until your Herbes tube dampers arrive.

Now this only works on small tubes like 12ax, 6922, and 12au with a point on the top of the tube.

While it may work on larger tubes the greater heat might be a problem

Take regular "mortite" (putty) and roll it in a ball the size of a large marble and simply pushing it down on top of the tube using the sharp tip of the tube to keep it in place.

I haven't experimented with putty size yet, but with a ball about the size of a regualr marble (or slightly larger) on three of my tubes, I swear the sound was cleaner (but oh so slightly)

When I get over to the hardware store, I might pick up some more and experiment with larger and smaller amounts.

I just checked the "mortite tube dampers" and it doesn't seem like the heat softens or affects them in any way.  Skewering them on the top like that mechanically couples them and just has to do away with some vibration and resonances that affect them.

Or you can spend the dough and get herbes.

I suppose if you're real creative, you could even make other shapes and such to pass the time

What is the opposite of "cheapskate" anyhow??? Expensiveskate??  

[TheChairGuy]

Yep John, the Mortite Hats do indeed work...I've used them for years on signal tubes (not larger output tubes) like 12ax7's and 6922's and their like. Mortite ad Dennis are the name brands in the business (Ace carries Dennis, I think)  and the generic name is clay rope caulk (someone told me Home Depot brand is the least expensive out there - fyi).  I usually find the stuff in paint sections in Hardware Stores.

The Herbie's makes it a little better still.  I found once you do the Mortite Hat that the Herbie HALO Jr's achieve the same effect as the regular HALO's...saving yor self a couple bucks on each tube damper this way.

It can almost make tube gear sound like solid state...yet leaves the 'magic' that some find in tubes.  I'm not currently one of them, but I know the Hats do improve things  

Good tweak, my man.

[brady2004]

I use silicon (rubber?) rings on both the smaller dual triodes and the final tubes - whether 300B or 2A3 or whatever.   I get them from a retailer selling rubber rings (for use in automative engines).   Just make sure they're silicon.  They can resist heat.    My tubes don't "ting" when you flick a thumnail at 'em.  I get them for about P100 where I am  (that's about US$2 where most of you guys are).

[Gordy]

Excellent posts!  Just to expand on the O-rings...   both silicon and Viton are safe for use with power tubes being good to 400F/192C.  Buta-N and neoprene are okay for signal tubes, but rather borderline for high temp applications (225F).  I've measured skin temp. of 34's at 216F.  Kalrez would be the perfect over-the-top material, having been developed for use as O-rings in jet engines (600F), but at  $35 a pop... Not!  as it doesn't offer any rockwell advantage over either silicon or Viton @ $.50.

I still like Herbie's the best...  in black

HTH
Gordy