Damping valves

I read about these:

http://www.euroaudioteam.com/en/eatcooldamper.php

which mechanically damp vibration in valves, and I was skeptical but intrigued.

Anyway, I took a gamble and bought a set. Wey-hey! A very substantial improvement - not subtle at all - and it was noticeable immediately.

The sound seemed more coherent and lively with the dampers in place, and it sounded like band members were really grooving together, if you'll pardon an aged phrase.

By comparison, my amp (Art Audio Quintet integrated - ECC82s and 83s into EL34s) without the dampers sounded rather loose and relaxed on rock and pop. It was good, in fact the best amp I've ever had by a country mile, but now it's even better.

So....now I'm thinking about damping the output valves as well. E.A.T don't make anything for EL34s, so I'm looking at the Duende Criatura tube rings. Does anyone have experience of these?

 

They certainly look the part.............couldn't see a price on them but on the basis of if you have to ask you can't afford. Has anyone any suggestions for minimal cost tube dampers?

 

Well as it 'appens, I have.

I bought some off ebay from a dealer in the states (from whom I also I bought some RCA ecc82's). For approx £10 inc p&p you get a set of 8 dampers to fit one of five different sizes of valves. I got the one set for my input valves, but I'm probably going to get some for my el34's as well. I'm not saying there was a truly dramatic difference, but they definitely tightened things up a bit.

See the following url and 'other items' for different sizes:

http://cgi.ebay.co.uk/8-TUBE-DAMPER...851489010QQcategoryZ64629QQrdZ1QQcmdZViewItem

They don't look as posh as the EAT ones, but they're cheap and seem to have a +ve effect!!

 

I used some rings of blu tak. I'm not sure there was any difference though.

 

This was discussed a while ago, RS silicone o-rings are the business and cheap too

 

I wouldn't like to put that anywhere near power tubes

 

just as a matter of safety for people who may be reading the forum and not know, the outside of a valve can reach the temperature of an oven. Make sure anything you put on a valve has a very high melting temperature, and doesnt prevent air getting to the tube to cool it down.

I thought I should mention that as the forum has a lot of readers, many non members

 

tube dampers

I have used Blu-tac on the Jadis mono's for many years. It works just fine. Only for input valves tho.....put it on output's at your peril or is that puddle. I use marble size piece on the top squished down into the nipple of the valve and an approximately 4-5mm dia ring just above the half way mark on the body of said valve. No problems ever, aside from it drying out the surface a little but this is due to 10 6550's blazing just inches away.
It works as well as anything, it costs a quid. You can take my word if there was some special thing for reasonable money out there it would struggle to beat this anyway. eg tubesox remember those. I bought some like a muppet. Rubbish, utter rubbish. You can make your own if want to try for a fiver. Welding suppliers-Kevlar gloves-yellow-cheap and pure kevlar fibre. Cut the finger tips off......I'm sure you get the idea.

 

You can put the o-rings on pretty much any tube, they only cost a few pence and look better than blue tack

 

Am I bovered about the looks-Na, just music. Sillicone will perish and die. Blu-tac you can add other materials to it distribute those modes of resonance.

 

but won't the damping properties and hence the sound change as the blue tac ages and hardens?

 

Good question Robbo and the short answer is yep, but not much. At the end of the day your just adding a little mass and if you mix other things in to the blu-tac its just distributing the resonance across a broader freq range. It kills the high resonant frequency of the glass+armature structure in the valve as a whole. Well more or less.
The subtle change over time as it dries you wont hear or care about.

 

I've had great results with the Herbie's Audio Labs HAL-O tube dampers: Herbie's Audio Labs

They're relatively inexpensive and really do work. A lot of reviews/feedback on the site and I have to agree with most of it.

John (about to order some more to do the power amp now)

 

I'd seen the ebay jobbies......I may have a look at the RS o Rings got get a bag of fifty so would any body like to part chop a set. I'm looking at the Viton type for the signal valves.

rs 129-117 O ring,Viton,BS116........... thats approx 30p each.

I think you'll need at least 2 per tube

 

They're not that expensive, actually - £15 each from Absolute Sounds. I bought 4, so £60 has got me a substantial improvement on all my sources. Bargain!

To be fair, I suppose the usual caveat about "your system may respond differently (if at all)" applies, but my experience was grin-inducing.

 

Thanks ......I've ordered the viton's and see if my gear responds before I take things any further.

 

I have two of these on every tube, large & small. Very cost effective upgrade if you ask me.