Benefit of Tube Dampers/Coolers on 6H30?

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.

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.

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.

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.

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.([email protected])
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!

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.