Tube dampers

Anyone uses them, which brand ?

 

I use these:

http://www.soundlabsgroup.com.au/pc/EAT-Cool-Damper/Valves/Sound

The improvement was immediately noticeable and I'm very happy with them D

I'm trying to remember what my amp sounded like before I got the EATs - off the top of my head, things got clearer and cleaner . I remember being a) surprised that the improvement was so significant, and b) grinning quite a lot. At £60 for four (from Absolute Sounds) this was a bargain upgrade. BTW, the EATs only fit smaller (ECC82-sized) valves.

 

Apparentely the EATs dont even fit my pre tubes...

What about Duende Criatura tube rings or HAL-O...

 

You could also look at Pearl tube coolers, worked OK on my old valve phono.

 

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

 

They must cost about 10c each to manufacture.

How is that a bargain?

FWIW I use the red "Conrad Johnson" jobbies. About a dollar each from various dealers on eBay US.

DT

 

Didn't hifi news have an indepth article recently including testing and found that they made very little difference?

 

I think you're confusing that with speaker cables

 

Go get a set of high temp silicone 'o' rings you get a bag of 50 for £15 .....these work as well as most [except the really good ones and tube coolers]

 

June issue, page 92, Talking Technical. Article starts:

"In part 2 of this investigation into valve amplifier microphony, KH looks at valve damping devices. Can fitting a sleeve over a valve's glass envelope really suppress its internal resonances"

Its a 3 pages long with microphony impulse responses from a Prima luna pre and power amp testing Eat Cool Dampers, Pearl Tube Coolers, Tube Rings and no dampers with and without valve covers fitted.

The long and short of it was:

"If the results I've obtained with the PrimaLuna amps are broadly representative then the conclusion has to be that valve dampers- assuming valve microphony is audible in the first place- don't have a large effect....I think you'll agree that differences with the dampers applied are small. This doesn't mean that they are insignificant, but the valve damper that provides a convincing, say 20dB (10x) attenuation of microphony doesn't exist. Given that a device attached to the glass envelope is being asked to damp vibrations of the electrodes within, this is hardly surprising. But dissapointing nonetheless."

The wave files are here:

http://www.audiosignal.co.uk/wave.html

 

As I suspected; but, given that silicone 'o' rings are about 33p each, I tempted. Zanash, have you had any degradation problems with yours?

 

I ordered this:

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

 

I paid about 50p each for silicon rings from a seller from the states on ebay, and I thought I could detect a positive difference..... At about a five or six quid for all my preamp valves (2 per valve) I figured it's worth a go, and I have no regrets...

These ones in fact:
http://cgi.ebay.co.uk/8-TUBE-DAMPER...ryZ64629QQssPageNameZWD2VQQrdZ1QQcmdZViewItem

Not as cheap as buying in bulk in the UK, but I didn't want fifty!

 

Thanks, la toilette - I've just taken a punt. No problems with heat damage, I presume....

 

For small signal tubes just use wide heatshrink. Works and costs next to nothing.

Look like this in my phono stage:

 

Nope, I only have them on my ecc82/83's though, not on the output valves.

 

None what so ever ..........They are high temp ones good to about 350f if memory serves.

I've a bag full somewhere pm if you want a few to try.

As to there effects ....I agree the difference is not huge but things do sound sweeter . You only need to tap the glass enclosures with a rubber ended pencil to hear how microphonic.

An interesting test is to tap then fit the o rings and tap again ! you can guess the results

 

First an apology if this post is a wind up - it is not meant to be!

But the above quote is a gift from heaven so use some lateral thinking! I'm afraid I can't say any more than that!

 

RobHolt....

just spotted the pics ...a couple of makers use heat shrink on there tubes, though the ones I've seen fit them higher up near the shoulder. Supposed to be quite good but the charge a lot more for them over the naked versions mesa boogies ! thats them see....

http://www.hotroxuk.com/store/erol.html


£26 pounds a throw ! The heatshrink looks quite thick maybe two layers !


Did you fit the paper in oil caps ?

 

Hi Zanash, your PM box is full....

Alex