Benefit of Tube Dampers/Coolers on 6H30?

A quick search of the forums led me to the belief that the effectiveness of tube dampers and coolers is dependent on the tubes used.

I'm auditiioning an Ayon CD-2, and want to really hear what it's capable of before deciding to keep it (which I'm leaning toward anyway).

I'm curious about how beneficial dampers and coolers are on 6H30 tubes. And if they are helpful, which to use? I saw Mrtennis recommended the EAT coolers/dampers ( another thread, and he stated they tamed some of the mid/treble glare in his unit, which is exactly the issue I have with the performance of the CD-2 right now. OTOH, it seems Herbie's halos ( the most popular choice, although I sense the EATs are fairly new.

Then there are these, with a choice of brass or copper:

These, which look very much like the EATs, but cheaper:

These for the *really* brave:

And I recently saw some coolers/dampers somewhere that looked like the EAT and pcX, but longer, covering almost the entire tube, although I can't find them now.

I'm a bit lost. Are any of these products superior to the others? Do any of them change the sound in different ways than the others? Would it be beneficial to combine products, such as Herbie's and the EAT on the tubes?

Are the 6H30 tubes so good they don't suffer from microphonics and other common tube characteristics such that the use of any of these devices would render little if any beneift?

Thanks to all for your thoughts.


I am running a BAT VK 31SE with NOS 6H30 tubes. Presently, I am using Herbie's Tube Dampers with success. It sounds a bit better than the naked tube. I have also tried brass dampers but did not like the sound, a bit dark and lifeless in my system. FWIW.

Best of luck!
I 2nd the Herbie's ultrasonic damping instruments ( these are the newer ones from herbie's) I use them on my ARC LS-25mkII. The difference is not huge but if you can hear, they do sound better than the naked tube.
The 6H30 based designs that I've heard had the "glare" you mentioned. The soundstage is bigger, images have greater separation and dynamics are increased, impressive at first listen, correct? I also found the decay to be very rapid and harmonics thin and short. Not SS but not tube.

I have a ARC CD3 MKll (SS) and wondered if the ARC CD7 (6H30 based) would provide some tube fullness to the mids and highs, specifically for female vocals. A friend brought his over and within minutes I wanted to pull it for the CD3 MKll .

I also owned a new amp with a 6H30 based impute section, it had the same traits, it's been sold after 550 hrs break-in. I wanted it to work but...

I checked out Stealth Cloud "9" P/C's they appear similar to V/D three wire design which I have owned. I found the V/D PC's were an aggressive cord and produced a similar sonic presentation to the 6H30 gear I mentioned. I pulled the V/D for a "stock" cord , better( in my system w/ my CDP). I bought a Purist Musaeus lower end of the line P/C trying to find a warmer less in your face cable. It worked great for my digital, did it create an $8500 CDP? No, but it did help with fuller highs, mids and bass.

I think the 6H30 has a hi-fi not a hi-end sound. I haven't heard any BAT gear
so I have no experience with VK's 6H30 designs.
PS I'm ready to take my whuppen like a man!!!
Hmmm. Interesting observations, Samhar. I'm away on business, but you can bet I'll try the stock cord on the CD. I'm using the Cloude 9 speaker cables, but Stealth Dream power cords.

You're spot on about the sonic traits I hear with the CD-2. That concerns me, and leads me to seriously question whether break-in will alleviate this issue. I'll break the unit in as well as I can until my 15 days are up to see what happens.

I've corresponded with others who have owned Ayon CD players, including another person reviewing the CD-2 right now, and no one else seems to hear what I'm hearing. Yet none of my components could be considered bright or harsh. My KCI Silkworms are temporarily replaced by Gabriel Gold Revelation interconnects, as my CD-2 had some shipping damage to one of the XLR connections. I should note I'm using a number of room treatments and don't hear any glare or harshness from the Cary, so I think I can eliminate the room as the cause/a contributor to the undesired sonic traits.

I'm now shying away from tube coolers after reading elsewhere that they may actually cause damage to the tube by displacing and concentrating the heat to small areas of the tube. I've also received some input that dampers don't have the degree of effect on 6H30 tubes that they have on other tubes, but I'll likely still try a quad of Herbie's Ultrasonic 9 dampers nonetheless.

Still interested in input from other users and keeping an open mind. Thanks to those who have already shared thoughts!

I think your hearing exceptionally, it's hard to stay the course with everyone's impute ( some probably have a horse in the race) and keep saying to yourself that just sounds forward and bright to me!! I live in a hot bed of ARC systems with people that love and defend "that" sound. Triple expresso vs Single Malt Scotch.
I didn't mean to say changing cords will make that great a difference with 6H30 design gear. It will just be less forward and thin not a change in the basic sound with the stock cord.
The tube dampeners will only take away what your trying to get, a rich warm tube bloom.(something that will never happen with the 6H30)
I pulled the dampers off the 6922's and 12AX7's in my Calypso preamp to get a richer sound. I like gear with 6922's, 12AX7's ETC. that permit me to modify the sound depending on my moods or the type of music I'm listening to, something you would be giving up.
Keep us appraised of your progress.
Samhar, I'm reading your observations about the 6h30 tubes and the first question I have is what 6h30 tube did you listen to? As you should know, if you don't, there're several different versions of this tube. Have you heard all of the different 6h30's that are made?
It would seem to me that if you haven't then you can't make a universal statement about "that" sound as you call it.
For example 6h30 dr's as well as the BAT 6h30's sound much better than the electro harmonix and sovtek 6h30's. They're much smoother and warmer and sound quite good to me in my system.
Just because they didn't sound good in your system doesn't mean they won't sound good in someone else's.
In the final analysis its all about system synergy. Other things affect sound not just tubes! Such as interconnects, powercords, speaker cables, proper component matching etc.
Its just as hard to stay the course with your inpute as it is with anyone else's. We all have opinions and no one opinion is any better than another's.
Aggielaw, listen for yourself, no one can tell how something is going to sound in your system. Experiment with other versions of the 6h30 and then make your decision.
That's my advice.
Eee3 the stock 6H30 tubes in my now sold ARC VS-115 amp which I wanted to like and gave a fair amount of time to break in but never could quite like. I think the designers are stuck with this tube and are doing the best they can with a tube that's sonic characteristics aren't close to the 6922, 7308, 6DJ8,12AX7 and 12AU7 etc. They can't design for these tubes because there aren't enough around and so far the Russians and the Chinese haven't been able to produce tubes with comparable sonics. My experiment cost me a fair amount of money and my intention here is to back Aggielaw's impression of the sonics of the CD 2 , not to change his mind but to support his experience by making him aware that " its not him" others hear similar things!
Samhar, you just supported what I said! You were listening to stock 6h30's. Nos 6h30's are much better than the stock ones, just as nos 6922,6dj8,7308's are considerably better than stock ones, as well as after market or audiophile quality powercords are better than stock cords.
My point is give an accurate account ie; I only tried stock 6h30's not nos 6h30's. You didn't say that! which would lead someone to think that that's indicative of all 6h30's tubes.
Sorry I was not aware that the nos tube were an enormous improvement over stock 6H30's. If there is a big difference in sound then Aggielaw might want to borrow some from the dealer so he knows what he's buying.
Anybody try a 6n6p tube to replace a 6h30? There are few individuals that swear by it. Drop in and cheaper than a 6h30.
I have yet to get the nerve up to do it. BAT says no damage to try but they do not recognize any benefit.
Aggielaw how's the listening progressing?
Slowly. I've had to travel quite a bit for work, and the unit is headed back to the dealer to have an XLR output repaired that was damaged in shipping to me.

I got the system to sound much better by adjusting the speaker positions. I'm still not sold on the unit, but a few days of listening and tweaking when I get the unit back and am home long enough - which should be about March 11 - and I should know something.
Nos 6h30's are much better than the stock ones, just as nos 6922,6dj8,7308's are considerably better than stock ones
My experience with the 6H30 DR vs. the latter Sovtek labeled 6H30 tubes in a BAT 31SE indicated the differences were minimal at best. But differences between various 1950s and 1960s Amperex, Telefunken, Valvo, Siemens, Phillips 6DJ8/6922 compared to Sovtek 6992 in state-of-the-art gear like the Aria WV's line and phono stages, Aesthetix Io/Callisto and older ARC gear like the SP-10/MCP-33 are HUGE. The claims of major differences with 6H30 tubes are way overrated.
Overrated to who Jafox? Just because you don't hear a difference doesn't mean that a difference is not heard by someone else. Everyone's system is different. The only person you can speak for is yourself and how it may have sounded in your system!
There obviously must be a huge difference or folks wouldn't be talking about it.
That's the problem with this site, too many folks speaking their opinion as if it were a universally accepted fact.
This hobby is and has been about how a specific component sounds to that particular person in their system period and as I stated to Samhar if you haven't tried all of the different variations, then you can't speak from experience.
The claims of major differences with 6H30 tubes are way overrated.

I second that.
Eee3, I did not say I did not hear a 6H30 difference. I said the difference was minimal compared to the major differences between 6922/6DJ8 for which you related to. Please note again that I wrote "claims of major differences", and not, "claims of differences".

If you read the various ARC LS26 and Ref3 threads where people have written about differences with 6H30 tubes, you will see that the consensus there that the observed differences are minimal. Again, my comment was not of absolutes but rather a relative vs. differences between tubes of other types.

Compare an Amperex 6922 PQ or Telefunken 6DJ8 vs. the stock Sovtek 6922 in your ARC PH3SE. And then compare the 6H30 DR vs. common Sovtek 6H30 in your ARC LS25 II. You will then know the point I tried to make before.
Jafox, obviously you haven't read my other thread responses to this issue or you would know that I have and have tried every iteration of the 6h30 that's out there. To include: Sovtek, electro harmonix,Bat technology and the Nos 6h30-dr's. (I haven't had sovteks in my LS-25 in over 3yrs.)
I just recently compared a new pair of electro harmonix 6h30pi gold pins(100hrs. burn-in)to a 5year old pair of Bat 6h30's and the bat's are still considerably better! not minimally better. The 6h30-dr's the same result.
I have a audiophile buddy who has an LS-26 and his experience is the same. In fact he just purchased 2 more pairs of 6h30-dr's he will tell you the same thing.(
Also, I've not had sovteks in my PH-3se since I purchased it 5 yrs. ago. but I have had in it Amperex 7308PQ's 6h23n Russian, matsushita 6dj8's,amperex orange globe 6dj8(mid 1960 vintage) and currently siemens-halski 6dj8's, so I've made the comparisons you are talking about.
I am not a novice, I've been in this hobby 25 plus yrs. and speak from experience not from what I've read or heard from someone else. And as far as your point about the threads on the LS-26& Ref 3, I'd be willing to bet(an I'm not a betting man)that the majority of the folks only compared sovteks to electro harmonix 6h30's (just as Samhar did) an in that regard they're right the difference is only minimal.
Finally, the 6h30-dr's are currently selling for $250-$310 pr. as are the amperex 6922 PQ's an the telefunken's(to use your comparison) and the siemen's for even more. So, my question is if they're not considerably better, why are folks buying and selling them for that price?
I certainly wouldn't pay that price for a minimal difference!
Anything new or old to share about the CDP's?
Hello, Ck. I decided to give the 6N6P a try and ordered a dozen from a guy in Russia. I have them running in my Ref 2 Mk II with excellent results. I have had my preamp since it was new (so 8 years or so) and these tubes have added warmth overall and really sweetened up the mids. I paid about $4 per tube with shipping.

Any downside to the sound?
Since this thread started I purchased a C/J Act 2 (6H30p) that outperformed my previous Aesthetics Calypso (12AX7, 6922) and for many months I have been satisfied with the improved, dynamics, extension and inner detail the Act 2 brought to my system.
In an attempt to change/improve I rolled in some Electro Harmonix 6H30pi's that were fuller in the mids but less extended and dynamic than the stock Sovteks a trade-off I wasn't willing to make so the Sovteks went back in.
I'd held back from trying NOS Reflector 6H30p-DR because so many have said they weren't a big improvement if any improvement at all.

You are correct on many counts!
I made a blanket statement without full knowledge/experience and to any that may have been negatively effected I apologize. (I apologized to Mr Tennis months ago for a related statement)
The NOS '83 Reflector 6H30p-DR's are an improvement over the other 6H30p tubes in my C/J Act 2 and by no small amount!!! I think the difference is comparable to the differences between a Sovtek 6922 and an Amperex US 7308 PQ White Label in all respects.

If you haven't tried the NOS DR's it may solve what was bothering you or simply improve what you already like, they added a good amount of "fullness" as well as dynamics and extension to my system.
Samhar, thanks for your response. I appreciate your honesty in admitting you had made a hasty judgment,a lot of folks would not have done that. So for that kudos to you! The only thing I was asking you to do was make a fair comparison.
When I started in this hobby 25+ yrs. ago, all I wanted to do was hear good music through good equipment( or at least the best I could afford) In that time, I have found that there're things (tweaks)you can do to improve the sound of your system that are cost effective or not as expensive as going to the next component in the upgrade path. Inserting good tubes(Nos) is one of them and the 6h30 dr's are an example of that.
When I decide to participate in one of these forum threads, I do it only to impart my experience and knowledge( what little I have)and to help someone gain the same benefits or improvement in their system that I have. I think that's what this forum was created to do and I think that's what most folks who participate intent is as well.
Unfortunately, I think most folks who don't think that the 6h30 dr's make that much of difference have only tried them in amps (and I will admit that in amps the difference is not as dramatic) or did as you did made a rush to judgment but in linestages and preamps, the difference is as you put it significant and not by a small amount!
I hope that others will benefit from your experience as well.
I've done a lot of tube rolling with my ARC gear and to me 6H30 DR's sound better than the current Russian alternatives. I also prefer ARC's tube rings to Herbie's.