Herbie's tube dampers vs O-rings

I was wondering if anyone had really done a good comparison between Herbie's tube dampers (the kind with the tungsten ring) and two or three silicon o-rings.

If you have a decent amount of tube gear, Herbie's dampers can get pricey at $30 a pop. In my case it would cost me about $600 to get the full Herbie treatment vs like $20 for the o-rings.

Many years ago, when I first tried the o-ring type dampers, I was stunned at the improvement in my ARC SP9 preamp. At the time it was the only piece of tubed equipment I had. Since then I automatically put two o-rings on my tubes but have never evaluated the Herbie types.

 

I've never used tube dampers and have wondered if they really made a difference. When you say improvement I'm wondering what kind of improvement?

 

No way that I'd pay $30 for a tube damper. I have used o-rings for years. If you want to experiment, you can fabricate couple of the halo style very easily. I can't see any advantage there; it doesn't really add mass, so it doesn't seem like it would fundamentally change the resonant frequencies or damping vs an o-ring or two. I would like to think that if any sort of tube damper, whether weighted or not, really made a huge improvement in sound, it would be standard equipment inside of high end tube amps such as those by ARC. Most companies that use anything, use an o-ring or a type of wider band that is basically a heavy, silicone grommet. It would become rather economical to add a more advanced type if it made a significant difference, due to the scale of production. The next time that I get around to it, I'll probably look into some larger bands rather than using a couple of o-rings myself. Not sure that there would be a sonic difference but it will only be a few dollar investment for a set.
-Bill

 

O-rings dampen the glass envelope and absorb some of the vibration that they can be subjected to. When a tube is vibrated, it causes some microphonic effects that are heard as noise and can smear sounds, lowering resolution. Using o-ring dampers will make the tubes less resonant and thus lower the noise floor in the amplifier's audio output. It doesn't cure thermal noise, just helps with microphonics. The commerically available varieties do the same thing and come in several shapes and sizes. Some other types include heat sinks. I am not sure the accordian types would be as effective against microphonics as they have a hard, metal portion held against the glass envelope.
-Bill

 

Thank you for the explanation.

 

I must say I've never found simple silcone o-rings to be of much use at all in tube damping, and I've tried. Herbie's, by contrast, I've found to be incredibly effective in places where it really matters -- like combo guitar amps. Why it works, why there's a difference, the mechanical engineering of why a halo type damper works better, I have no idea; and I'm inclined in almost all instances to eschew all kinds of expensive and silly-seeming accessories at high prices. But in my experience the difference here isn't small -- I've found o-rings all but useless and Herbie's to be very effective at ending the kind of smeary, excessive brightness and even sometime physical rattling you get in guitar combos. On hifi gear I've found all kinds of damping to be far less useful, but still I've found 0-rings to be more or less no better than using nothing.

 

Nobody asks you to spend $600 for a full suite of Herbie's. You could buy them just for input tubes and see if you like them more than simple o-rings.

I personally have Herbie's on all (13) tubes and would not want to be without them. Plus they last forever.

 

I have Herbie's tube dampers on my SCA-35, and I was truly amazed at the improvement in sound. Everything clearer, images more solid, better separation, all that stuff. And I was skeptical going in. You don't need the $30 ones for every tube -- only the power tubes that get really hot. The $15 ones work fine for preamp tubes. I have never done a direct comparison with o-rings though. I will say that Herbie's products actually deliver on their claims, in every case, IME. For example, the Herbie's tt mat is superior to every other one I tried, and I did do head-to-head comparisons with a whole bunch of others. Their isolation products work extremely well too. And their customer service is second to none.

 

I have used both. I also paid $12 each for my Herbies, if I recall. I would take the rack and other isolation into account. My old amp had cooling fans and I used double Os on those power tubes and felt like they helped. I like the Herbies on the preamp tubes and I have none on my power tubes at the moment.

 

Bill gave you the full explanation, but basically its less distorted.

 

I guess I'll have to check the website again, I only remember seeing the $30 types.

A while back I tried the tt mat and the CD disc damper ring. I didn't think the mat was better than the Ringmat on my LP12, but it did beat the felt. So I sent it back, Herbie was surprised. Anyway I loved the CD disc damper ring that goes on top of the disc. Only use if for playing SACDs now that I have a Transporter, but it works.

 

I was going to recommend the Valab teflon tube ring dampers but the product is not listed on their E-bay store at this time. IMO- worth contacting the seller to check on availability as these rings are excellent- they don't negatively color the sound at all.

 

I had good luck with the Herbie's tube dampers in the past, but haven't tried them on my VSi60 which has the silicon o-rings.

 

Yeah, the only one's I've ever used are the $12-$15 types and pretty much only the older ones with the plastic, not titanium rings, at least for preamp tubes.

 

Well, I might have to spend a liitle money and go with Herbie's.

 

I've tried various o-rings with little to no positive effect. I've tried Mapleshade dampers and they work perhaps too well, deadening the sound noticeably. The Herbie's dampers (some bought years ago when cheaper, some recently) work excellently.

 

I tried a batch of Herbie's dampers on my last tube amp and I could not hear a difference with them. Several times, I slid a damper onto a tube while it was playing to see if I could hear a change but had no luck. Because of this, with my new tube amp, I didn't even bother with them.

 

I have only used Silicon O-Rings, and they work well to kill the mechanical vibration where the internal bracing contacts the glass envelop, and that's all I need really, mainly on some highly microphonic small signal tubes. Have them on the 6H30's as well, even though they are not bad in this respect to begin with.

Need to try Teflon ones next, the Silicon ones go hard after a while exposed to the heat.

Though it looks like for heat, Kalrez seems best with a max temp of 288c, not sure what it is like as a dampener, will need to look into it more.

 

Update.
Last night I replaced the silicone orings on my ARC VS55 power amp with Herbie's Ultrasonic RX, all 7 tubes. I was pretty stunned at the improvement. I had previously thought that my amp was running out of power when I turned things up a bit, after all its only 50 wpc and I don't have particularly efficient speakers (87 db). I was very wrong, now things are super clear at all volumes. Very impressed. Now I have to do my ModWright stuff.

 

that is a good description of how it counts