Do tube dampers improve sound?


I recently purchased a tube pre-amp and several NOS 6922 tubes (EH, JJ Tesla, and Philips). Should I consider buying tube dampers? Do they really help the sound? Thanks
128x128vlad1456
I like the sound improvement of the Herb Audio dampeners. And they are inexpensive.

R.
I have no experience with tube dampers, but here is a link to some info about them:

http://www.magnan.com/pages/tweaks/tubedampers.html

You might also do a search on the Audio Asylum "Tubes" forum to get some more opinions. http://www.audioasylum.com/audio/tubes/bbs.html

Holly
I would be lying if I told you that I can hear any difference, but like chicken soup, it can't oit! I have Herb's on my preamp and Audio Research rings on my phono section. Since tubes are microphonic to some extent, it does make some kind of sense to do what can be done to reduce these effects. The other consideration is price: they are normally reasonably priced, so it makes no sense to be without. BTW Herb's are easier to remove; the ARC ones get pretty soft with heat and tend to stick to the tubes a tiny bit. Just one man's opinion.
I've done well with Herbies Halos as well. However, it is important to note that the use of Herbies Halos is not an exact science. While there is a recommended position for them, you can and should experiment with placing the Halos at different positions on the tube to see what works best for you. I have used the rings mentioned in the other thread and while I feel they are a worthwhile choice, the Halos were better for me.
I have found that the very heavy brass tube dampers that Andy Bouwman of Vintage Tube Services sells make an audible and positive difference in the EF 86 tubes in my preamplifier, better focus of images being the primary benefit.
Tube dampers are primarily used to prevent or minimize microphonics in small signal tubes such as 6922's. I would not go overboard here and spend alot of money.
All I can say is, try it for yourself and see. I have used them on and off in my equipment, and there were occasions where I thought they made a nice improvement in focus and clarity on some tubes, but on other equipment it took the "life" out of the system. The dampers will be tube and equipment dependant.
I use the Herbies Audio Labs Hal-o dampers on the 6922 tubes in my ARC LS-15. They did make a difference. They cleared up the soundstage a little and separated things a little better, but don't expect night and day difference with 6922 tubes that are low noise and low microphony, such as carefully selected and properly matched set of EH6922 tubes for example. WHats good about Herbies, is they come off easily and the never stick to the tubes due to heat.
http://herbiesaudiolab.home.att.net/
I used Halos on my Tenor 75OTL's. The Halos made the single biggest sonic improvement I've ever heard in my system. It's astonishing how much distortion I believed was in the music was eliminated and enhanced clarity, detail and lower noise floor I got.

It was shocking. Now how do I fit tubes into those DarTZeel's?

Then I could improve it with Halo's...
It would seem that, as with most things, we just need to try the dampers out in our own systems to see if they make a positive difference. The Herbies do seem to be the way to go as the price is minimal and most of the posters in this thread have had a good experience with them.

Let us know what you decide to do, Vlad1456.

Holly
I'm trying Herbies Audio Labs Hal-o dampers the Black Nylatrons on my Aesthetix Calypso as I write... and so far so good. They quiet down the pre amp somewhat, unless I'm hearing things (that are not there) or is that... NOT hearing things that were there?! Anyway, I feel that they are a good value, so far. Now to try them on the Rhea phono amp.
Happy Listening!
Hey Roger,
Tube dampeners make a noticeable improvement in performance. They tighten the bass, clear up the overall sound, and reduce microphonics. Definitely worth it, and they are cheap. Used them on my AES/Cary pre with great results.
So what is up with your system. I see you have a Dynaco tube pre.
Mike
I guess if I have to strain to attempt to hear a difference
I write it off as a bad investment. I put Herbies tube Dampers on my entire system (all tubed at that time) and failed to hear any improvement. The other thing I noticed is that the dampers used on my kt 90's got sloppy with use.
They are sagging on the tube and not really holding onto the tube. On the other hand herbies grungebuster is the best tweak I have ever tried. For 16.00 it made a large improvement in the sound of my cd's.
I used the Herbies dampers too on my tube integrated and have to say I could'nt hear a difference. Interestingly, HiFi News here in the UK, did a technical report on a number of tube dampers, including the pearl ones, though they are coolers too of course, in this months edition. They checked for microphony with and without the rings and found very little difference. Does'nt mean they are right of course, accurately measuring these things is'nt easy.
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I have high efficiency speakers and SET system and tried dampeners and found them to restrain(soundstage shrank) my system.I took them off and am happier for it.They also took the air and spaciousness away i felt.
I use very heavy brass dampers from Vintage Tube Services on the four 6SN7s in my Rouge 99 preamp. I have switched them in and out and used them with a variety of 6SN7 types.

I can report a tremendous sonic benefit. Bass is dramatic both in depth and definition. The soundstage is defined. With the dampers, highs are pleasant, not harsh.

I won't use tubes without them.

I do have the Herbie Halo dampers on the small signal tubes in the Zeus power amp. I do not notice much of a difference there, however.
There is a noticeable difference when using them with large power tubes (2A3/300B/etc), especially when direct-wired in SET configurations. The larger the tube, the more difference they make, in my experience. Whether or not you like that difference is obviously a matter of personal preference.

If you doubt the effect, put one around a slightly microphonic 6922 and listen to what happens. Hocus pocus, my hiney.
I find it makes a difference where you put them. Dampers seem to work best near the top of the tube, not in the middle. Hey, maybe that's where the "top hat" idea came from.

But thinking of the glass as a transmission line (or guitar string), this makes sense. You minimize reflections, and hence resonances by damping the ends, where refections occur. In fact, some of the spots in middle (or harmonic fraction thereof) could be null points and have no effect. Depends on the resonance mode, if fundamental or higher. Only way to damp them all is to do it at the top or bottom.
I am not saying that the dampers work or don't work. I, too, THINK I hear an improvement when using Herbie's Halos on 6dj8-type tubes. It really makes little sense, and is kinda sickening actually, that the sound of, say, a $5K phono stage which is said to be the "end all" by its maker and ardent users, could be so dramatically improved by a $10 plastic tube ring. There is just something odd and wrong with that equation. (I realize that such oddities aren't restricted to tube dampers).
Virtually all vacuum tubes are prone, to some degree, to distortions caused by microphonic vibrations, and some tubes internally generate their own microphonics. This is true whether a component costs $200 or $20,000. Microphonic distortions will vary from one kind of tube to another and according to other factors such as microphonics-induced distortions in capacitors and other electronics, which might "mask" a cleaning-up of tube microphonics. Audio improvements are quite subjective, and what might be a minor improvement to one could be quite major to someone else. Even so, the affects of tube dampers varies hugely; sometimes the improvement is miniscule or barely perceptible, and sometimes very upfront and dramatic.

There is no "end all" product or accessory; everything in an audio system must synergize together to achieve the desired end result. If tube dampers are not the "cat's meow" with your system or not really worth the investment, send them back. It seems likely, however, that if you "think" you hear an improvement, you do. You might consider keeping them as part of an overall vibration-control solution.

Thanks,

Steve Herbelin
Herbie's Audio Lab
I even noticed that the placement of tube rings on the tube matters. If they are placed right in the middle of the tubes, they become too much of a good thing. But at the very top of the tubes, they provide a nice improvement. Although I didn't hear any drastic tonal changes, but separation, definition of instruments and overall soundstage clarity definitely improved. Dressing all the tubes in the preamp with Hal-O damping instruments doesn't cost much and I think it's a worthy improvement.
At least in my system it was.
Once again I have to make my plug for trying the inexpensive solution first. I got 50 industrial grade silicone o-rings from here:

http://www.marcorubber.com/material_selection.htm

for $10 plus shipping. I have a preamp with all octal tubes, so the S1000-216 o-rings were the perfect size. I use 2 per tube, and they make a noticeable difference in microphonics and smoothing out the bass, which is a little woolly without them. Would Herbie's or one of the other far more expensive dampers be better? Maybe, but I'm not sure my rig has enough resolution to prove it. I'm happy with my cheap o-rings.

Plus, you can get them in about 10 different colors to match your decor. :-)

David
Steve:
I hope you didn't infer from my post that I was questioning the efficacy of your dampers in particular because that certainly was not my intention. I have your Halos and, like I said, I think they have been of benefit. As an aside, I like your phono mat to an even greater degree! :-)

My real point is that when a manufacturer designs and builds a piece, they virtually always wax poetic about the sound quality. But, if the sound can be improved so dramatically through the use of tube dampers, you’d think they'd have already factored that into the equation. I guess what your saying is that the improvement realized depends more on the tube used than the equipment, so dampers should be assessed accordingly.
There must be a good reason that ARC delivers tube dampers on certain tubes for certain equipment (e.g., pre and phono).
Using the Halo's is more like an art than an exact science. There is no real formula or equation for success. You have to play round with them and see what, is any position, works best. They may only provide minute improvement or could make a huge difference based on a number of factors.

I was told by Brendan at Tube World to think of a tube like a car antenna. Closer to the base the less flexible it is. However, closer to the top is where it is most likely to sway. That is why a lot of these tube tweaks seem to work best at the top of the tube. I use my Halo's about a third of the way down from the top. Best results have been with my phonostage. They did not affect my tube preamp as much.
Steve, thanks for allowing me to return the teflon tube dampers and exchange them for the nickel dampers. You have integrity that is too often missing in high end audio.
I also enjoyed talking audio with you for at least an hour
when I purchased your grungebuster. Your grungebuster was the most effective tweak I have ever tried and an incredible bargain. I had upgraded my preamp to the CAT Ultimate MK2 and my DAC to the Audiologic 24MXL just before purchasing your grungebuster. That tweak was a greater sonic improvement that the $11,000 upgrade! Thanks again.

Bart
I use Herbie's on the input 9-pins of my VTL mono's and like what they do, regardless of whether the tubes seem overtly microphonic or not (as determined by the tap test). The dampers help with better articulation of vocals, for instance, with less sibilant edge and more palpable image focus/dimensionality; give a clearer, 'calmer', more naturally stable soundstage that's less perturbed by what's going on musically; lend better purity, indivuated tonality, and detailed realism to cymbals; and generally reduce a slightly forward excitability in the presence range, making listening easier at higher volumes. As these symptoms are all things which can be attributable to resonance in tubes, I'd say the dampers do their job -- you hear the tubes less, the music more. I don't think this effect is necessarily unique to Herbie's product vs. the soft rings made by others, but his are probably easier to move and remove, don't bind to the tube, look nice (if your tubes are in view), and still fall under the catagory of "cheap tweaks". Not a dramatic improvement for me, but easily more than worth their small cost.

When I ran a tube preamp, I didn't have the Herbie's, but tried Pearl tube coolers with the woven graphite undersleeves. This product probably works for reducing heat build-up (I also used them on some power tubes, but can only guess at, not measure, their effectiveness), however I wouldn't look to the Pearls as an anti-resonance treatment for small-signal tubes. If anything, they are prone to making 9-pins sound more resonant, not less, and these tubes generally don't produce enough heat to make any reduction worth the cost or sonic tradeoff. No audible problems when used on power tubes though.