Tube Dampers for EF86

[FunkyE9th]

Hello all,

I'm planning my next build. Looking at using an EF86. Any recommendation for tube dampers?

Anyone ever use this... http://thetubestore.com/eat-cooldamper.html

Thanks!

-Ferdie

[selloutrr]

I haven't delt with these exact dampers but dampers do help in certain situations mostly hi fi audio.
But not for $35 if you really think you need them check out the weber speaker amp parts page and buy a vibration ring for under a dollar and just make sure the amp has ventilation to cool. i.e. don't throw a packing blanket over it in the desert at high noon while you play at "11".

[LeeMo]

I just ran across this at 18watt.com. It was drawn by Heink at HBamps.
http://www.18watt.com/files/ef86_quiet.pdf

You can also use silicone o-rings for fuel injectors. I can't remember the size,tho. You can buy them at AutoZone.

LeeMo

[butwhatif]

You can also take an 1-1/4" piece of heat shrink tube, dia larger than the dia of the tube, and shrink it onto the top 1/2 of the tube.

[billyz]

I have been using heat shrink for years. I found it works even better than the o rings and cheaper.

[sliberty]

A while ago, I built an AC-15-ish amp with an EF86 channel only. The amp was squeeling a bit, and I was sure it was due to EF86 microphinics. So I bought other EF86's, even Cryo treated ones. And I bought tube dampers. And nothing helped. Then, I did what I should have done in the first place - I went looking for the oscillation, and solved it at the source. And now the amp is fine, with or without the damper. So the moral of the story is : don't even worry about dampers until you know you actually need them.

Good luck!

[Tubetwang]

A while ago, I built an AC-15-ish amp with an EF86 channel only. The amp was squeeling a bit, and I was sure it was due to EF86 microphinics. So I bought other EF86's, even Cryo treated ones. And I bought tube dampers. And nothing helped. Then, I did what I should have done in the first place - I went looking for the oscillation, and solved it at the source. And now the amp is fine, with or without the damper. So the moral of the story is : don't even worry about dampers until you know you actually need them.

Good luck!

Make sense to me.

[FunkyE9th]

Thanks all. I will try it without dampers 1st. It looks like I have several more affordable options if I do end up having issues.

[jaysg]

Anyone have a recommended ID for o-rings so there not too loose or too hard to put on? (There's no convenient O-ring store next the Radio Shack)

[sliberty]

When I bought mine, I got them from :

http://herbiesaudiolab.home.att.net/

He makese several different types, so you might want to email before ordering. They are very easy to put on and to remove.

Steve

[leaveitalone84]

http://stores.ebay.com/sandyphotos-Vacu ... idZ2QQtZkm

I use these on all my builds and most of my amps on the preamp tubes. Work great. I even use the EL34 ones in my Express Combo.

[Structo]

I bought some of those from Sandy's photo.
They seemed to help the EL84's in my Belair combo.

The only bad thing about them is if it is a tubes down amp, you can't use the wire tube retainers with the O rings installed.

I should try the Heat Shrink. That doesn't make them run too hot huh?
And does it give off any type of burning plastic smell?

[billyz]

The Heat shrink does not give off any burning smell. It is designed for high heat. Also, I have been using it for years without any problems. I have it on all the PI and driver tubes in my Conrad Johnson 11a for 4 + years no problems and sounds great.
I first saw them on Mesa Boogie 12ax7's in the 80's . I regularly use it on my V1 tube in high gain amps with out any problems.

Conrad Johnson uses the O-ring dampers in their preamp, but I switched tubes out so much ( to find the Holy Grail) . I ended up with Heat shrink on all the preamp tubes and it works as well if not better than O-rings. a fraction of the cost. you can even use BOTH !

[butwhatif]

Tubes have no problem with heat, shrink tube is the best, and costs nothing-

[selloutrr]

If you choose to use heatshrink make sure it's not the adhesive type!!!