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Tube dampers etc.

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Posted on April 8, 2016 at 13:05:37
throwback
Audiophile

Posts: 697
Location: Colorado
Joined: December 8, 2003
Contributor
  Since:
March 28, 2017
I have a pair of MA-1 Silver Edition mono amps that have been sent back to the factory and brought completely up to the latest configuration.

They are essentially perfect.

So, naturally, I want to keep messing with them.

A couple of Audio Magic (http://www.audio-magic.com/) products made a nice difference:
1. Audio Magic Cable Silencers [manufacturer's description , below]
Reduce unwanted vibration energy | Reduce noise | Enhance signal flow
Cable Silencers come in a set of 4 and are simply plugged into your negatve and positive speaker binding posts. They are not in the signal path, so their effects are entirely from passive operation.

The Silencers reduce Micro vibrations in the cable, reduce noise riding the signal, and greatly enhance signal flow.
What will you hear?
1. Incredible inner detail and Transparency
2. Faster and more dynamic Bass.
3. Wider and Deeper soundstage
4. A smoother and more musical experience

2. Premiere Super Fuse
This fuse is filled with a 1/3 anti-vibration material and 2/3 Super Black Out mixture for even better EMI and RF control. This fuse is just like the standard Super Fuse, only we've add our NEW i Core Technology to the fuse. [I put these in the driver circuit only: T.B.]

I have also put Herbie's Audio Labs http://herbiesaudiolab.net/ tube dampers on the ten 6SN7 input tubes.

Question: might I also benefit from putting tube dampers on the 28 6AS7 output tubes (at $29 each, gasp!)? Have any intrepid inmates tried this?

 

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RE: Tube dampers etc., posted on April 8, 2016 at 13:17:34
MrDerrick
Audiophile

Posts: 140
Location: South Central PA
Joined: November 25, 2001
I only use 1 pair of 6AS7s per M60 and I have Herbies dampers on them and they do have a positive effect.

Prior to using only a pair of 6AS7 tubes per amp, I spoke with Steve regarding dampers on power tubes.

He replied that damping 1/2 of the tubes will more than likely get you 90% of the gain you may achieve by damping all of the tubes.

FYI, I find that damping the CCS 6SN7 with 3 of Herbies Guitar dampers yields a nice result!

I will also ad that placing 4 Still Points Ultra SS under each amp will really surprise you!

 

I've used Herbies' tube dampers for decades including on my 'old'..., posted on April 8, 2016 at 14:42:40
jeffreybehr
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Posts: 4963
Location: Phoenix, Arizona
Joined: December 10, 2004
Contributor
  Since:
December 13, 2004
...M-60s. I heard the greatest effect--less edginess/hardness--by placing them on Vs 1 and 3. I don't know what to call V2, functionally, and V4 (and probably V5, too, in your amps with five-each front-end tubes) are Cathode Followers (= impedance-lowering buffers/drivers). I never noticed any benefit from damping the CFs.
 photo 06Jun2011_glowing_1280w_zpsh1ioxmmp.jpg
 photo Amppad with amp_1280w_zpskiy5odz3.jpg

I have a new pair of M-60s arriving Monday, and I've been thinking more about vibration reduction. Certainly the bottoms of the bottom plates will get a layer of SoundCoat the Thicker, as the last ones did.
 photo 11Jun2011_bottom damped_1280w_zps3lmb6yzb.jpg

As you can see in one pic, I used a steel block to mass-load the top plate between the front-end (FE) tubes; can't say I heard that do anything. But I'm also pricing blocks of custom-cut metal--copper, brass, or nonmagnetic stainlesssteel...

http://www.cut2sizemetals.com/copper/rectangular-bar/kbr/

...mounted with Herbies' 'grungbuster' vibration-absorbing pads...

http://herbiesaudiolab.net/gb.htm

...to place on the top plate. The new amps are Mk.3.3s with the FE tubes mounted in a 'T', while my last ones were Mk.2 chassis with the four tubes mounted in a square, so I don't know exactly what size I'll order, but they'll be 3/4" or 1" thick and two or 2-1/2" wide. I'll buy eight (four per amp) and place two near the FE tubes and one on edge between each column of output tubes. Steve Herbelin's comment that 'damping 1/2 of the tubes will more than likely get you 90% of the gain you may achieve by damping all of the tubes' makes sense to me, and I might try that.

On cable dampers, I'd be more inclined to put Herbies dampers on RCA jacks IF they're tubular metal.
 photo 2015Oct06_Neotec 1002s w KLEs at Oppo_1800w_zpsfseu2akx.jpg
Here they're on plastic barrels because I already had them.

As I wrote above, I'm getting more serious about reducing nervous-making vibration, so more pics later.

FWIW, my system benefits from less-than-average gain in the poweramps, and probably I'll be using A-S's gain-reduction plugs in V2. Also, I bought a box of 25 Russian Winged-C 6H13C output tubes thru eBay for less than $8 each; seller 'radiohouse' has none listed today, but keep your eyes open if you want some. Mine arrived promptly and in perfect condition.
----------
Tin-eared audiofool, large-scale-Classical music lover, and damned-amateur fotografer.
William Bruce Cameron: "...not everything that can be counted counts, and not everything that counts can be counted."

 

Audio Magic Cable Silencers, posted on April 8, 2016 at 17:29:46
Lew
Audiophile

Posts: 8778
Location: Bethesda, Maryland
Joined: December 11, 2000
Dear Chuck,
I can't argue with what you say you hear with the AMCSs, but you are basically quoting the website so far as the claims they make for this product. Just looking at how they are installed in the circuit, or not in the circuit, how the heck can they possibly "reduce vibration, noise riding on the signal, enhance signal flow", yada yada? I can't think of a single way in which they could possibly do any of the above. This does not mean they are a fraud, but some sort of explanation of mechanism is needed. (Maybe "Magic" is the right word.)

And now we have fuses that block EMI and RFI. I may be like the little kid who cannot stop asking questions, but... how?

Compared to this stuff, tube dampers make a lot of sense. But recently Ralph remarked to me that no damper can completely cure a microphonic tube. I have some very microphonic but great sounding KenRads in my MP1 and was asking Ralph about how to deal with it. Each one of them (6SN7s in the linestage) already has two O-rings on it, to no real avail. Herbie's dampers are used in my phono stage, nevertheless.

 

RE: Tube dampers etc., posted on April 8, 2016 at 20:31:30
throwback
Audiophile

Posts: 697
Location: Colorado
Joined: December 8, 2003
Contributor
  Since:
March 28, 2017
All I can do, Lew, is quote the manufacturer because I have no idea how the darned things work, fuses either.

But put 'em in, the system sounds "cleaner;" pull 'em off (easy to do, just slide them out of the banana plug openings) and you wish you hadn't. My golden-eared buddy ("fastest ears in the West") heard the same thing. I got them on a try-before-buy basis and they were fairly cheap so I tried them and liked them.

The fuse thing was more interesting. First place I tried them was in my DSA Phono II. Bingo! An immediate improvement. I tried them in my Atmas and I did not like the effect so I went back to stock. I tried them in my DSA Pre (-amp) and liked them again. So with AM fuses in phono and pre, I tried them again in my Atmas. This time I liked them. Go figure.

Jeffrey, I have the HAL dampers on ALL of my input tubes already. The question is whether I should put them on the output tubes as well. Your pictures do not seem to show dampers on any of the output tubes.

MrDerrick, your idea about damping only half of the output tubes is intriguing, if only because the cost is half as well. My amps are on Sound Anchor stands and Herbie's Tenderfeet. I had not thought about other feet, but maybe I should.

 

RE: Tube dampers etc., posted on April 9, 2016 at 11:07:55
Lew
Audiophile

Posts: 8778
Location: Bethesda, Maryland
Joined: December 11, 2000
Like I said, I respect your opinion, but it irritates me when manufacturers make such illogical claims with no attempt to back them up scientifically. However, maintaining silence is a good strategy, when you are trying to put something over on the public, especially the audio public.

 

RE: Tube dampers etc., posted on April 10, 2016 at 06:49:21
MrDerrick
Audiophile

Posts: 140
Location: South Central PA
Joined: November 25, 2001
I also have my M60s on Sound Anchor stands.
The StillPoint Ultra SS will make a startling improvement.
The effect is cumulative and I have them supporting all of my components.
Herbies Ultra Sonic RX are my preferred damper for my power tubes, driver and gain 6SN7s, tripple Guitar dampers on the CCS.
I have a MaxiPre tester that I can measure for gain and noise.
I find that perfectly matching the 6SN7 sections for gain is important.
The quietest tubes that I can find I use for the driver and CCS.
I have found that the gain section tubes sound better if they have a lower noise reading. ( more tubey sounding )

 

RE: Tube dampers etc., posted on April 10, 2016 at 10:04:40
Lew
Audiophile

Posts: 8778
Location: Bethesda, Maryland
Joined: December 11, 2000
Mr. Derrick, This may be in agreement with what you are saying, but if you have a way to measure "noise" of a tube, other than simply to insert it in the circuit and listen to music (which is not a bad way to do it), it's probably best to use the quietest tubes in the gain stages. The driver stage, and the circlotron output stage of the preamplifiers, does not add any gain, so in fact you can better get away with using noisier tubes in the driver stage. Same goes for the CCS, although I say that with less certainty; the CCS constitutes a very high impedance circuit, so it would block noice from the distal side, at least.

Apropos the talk about microphonics, I am facing the fact that I should get rid of my beloved KenRads from the linestage gain section of my MP1; they have become hopelessly microphonic, where once they were tolerably microphonic. They've gotten much worse lately. O-ring tube dampers are not helping at all. ("Microphonic" is not quite synonymous with "noisy", but it's one way in which tubes can add noise.) KenRads have all had this problem to one degree or another, but I am addicted to their sonics; I just try to pick the quietest ones from my diminishing stash. I am going to try Brimars next, which I know are NOT microphonic but are not quite as magical as KenRads.

 

RE: Tube dampers etc., posted on April 10, 2016 at 10:54:51
MrDerrick
Audiophile

Posts: 140
Location: South Central PA
Joined: November 25, 2001
Yes Lew,
One would suspect that logic would seem to dictate the tube which measures lowest for noise would be the best choice for V1 & V2.
But I have found that not all low noise measured tubes sound the best.
They can be very dry and dull.
My tester can measure the noise floor of a tube but you need to listen to it for microphonics.
I can tap on the tester and the value will fall, but I do not know what negative effects that may impart on the sound.
The MaxiPre has a pair of outputs that you can and I have, connected to the input of a pre to listen to what tapping on the tester sounds like through a given tube.
Some tubes just produce a "thump", while others howl like a banshee.
I believe that certain microphonic traits can be desirable in a tube.
What an MP1 needs vs my M60s may not be apples to apples.
When I had an MP3, I always used the lowest measured noise 7316s for the best performance of the pre.
Some of my best sounding 6SN7s in my M60s, are not the quietest measured tubes.

 

RE: Tube dampers etc., posted on April 11, 2016 at 10:34:41
Lew
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Posts: 8778
Location: Bethesda, Maryland
Joined: December 11, 2000
I absolutely agree that the quietest tubes are not necessarily the best sounding. (In fact, it would not be incorrect to say they are USUALLY not the best sounding.) Like I did say, I have stuck with the KenRads in the MP1 only because they are my favorites in terms of sound quality, but they have never been the quietest. They were somewhat microphonic from the get-go. And yes, a little microphony can be euphonic, but we as audiophiles are not supposed to admit we like that effect. (Joking.) Anyway, one KenRad has definitely got to go; the other may still be usable.

With me, it's a trade-off. I select first for sonics and then hope the tube is quiet enough to tolerate in the circuit. All I meant to add in the first place was the idea that noisy tubes in gain stages will be more evident than when the same tubes are used in stages that do not add gain, as driver/cathode follower and probably as CCS.

 

Lew, have you given the Tung-Sol roundplates a serious evaluation?, posted on April 11, 2016 at 11:40:26
jeffreybehr
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In my journey thru 'N7s decades ago, my first good-sounding find was the RCA, but that was quickly replaced by the KR VT-231/6SN7; to me the KRs were a little warmer balanced (a positive) and lacked nothing anywhere else. But then I found the TSRPs and discovered an even-more-attractive tonal balance and overall excellence. I had over two dozen years ago but then I had nothing to use them in and sold some; I was down to 15 until I bought the quad pictured below. But they too can be microfonic.

I'm retrieving a pair of Atma-Sphere M-60 monoamps today and plan to use probably two TSRPs in each amp.
 photo 2016 TSRPs 4_1500w_zpsfojuneca.jpg
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Tin-eared audiofool, large-scale-Classical music lover, and damned-amateur fotografer.
William Bruce Cameron: "...not everything that can be counted counts, and not everything that counts can be counted."

 

RE: Lew, have you given the Tung-Sol roundplates a serious evaluation?, posted on April 11, 2016 at 14:36:01
Lew
Audiophile

Posts: 8778
Location: Bethesda, Maryland
Joined: December 11, 2000
I don't use 6SN7s in the input stages of my monoblock amplifiers, but I do use them in my MP1. Last night I was going through my stash, and I may at most have only one TSRP. (Until last night, I had no idea what "TSRP" stood for.) I do have a plethora of KRs (mostly used and of several different origins), Brimar CV1988s, and Raytheon 6SN7WGT. One sample does not cut it. I may try any of the others; it's such a pain in the butt to dismantle my MP1 in order to change tubes that I prefer to make a decision however empirically and stick with it until the tubes go bad, as is the case now. I already use the Brimars in the circlotron section of the MP1.

I've got RCA 5692s, too. But they seemed a bit dull last time I had a listen, albeit that was not in the context of the MP1. A few Syls and GEs, too.

 

If you want to sell your single for, say..., posted on April 11, 2016 at 15:30:29
jeffreybehr
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...$75 and warrant that it's not dead, e-mail me at jeffreybehr(at)cox(dot)net.
----------
Tin-eared audiofool, large-scale-Classical music lover, and damned-amateur fotografer.
William Bruce Cameron: "...not everything that can be counted counts, and not everything that counts can be counted."

 

Any comment on Raytheon 6SN7WGT/VT231?, posted on April 11, 2016 at 18:59:17
Lew
Audiophile

Posts: 8778
Location: Bethesda, Maryland
Joined: December 11, 2000
Anyone?
Jeff, I sent you an email re the single TSRP.

 

I've never heard one. The instant I heard my first pair of TSRPs..., posted on April 11, 2016 at 20:34:41
jeffreybehr
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...I gave up on everything else.
----------
Tin-eared audiofool, large-scale-Classical music lover, and damned-amateur fotografer.
William Bruce Cameron: "...not everything that can be counted counts, and not everything that counts can be counted."

 

Boutique 6SN7s, posted on April 12, 2016 at 11:23:03
Ralph
Manufacturer

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Location: Minnesota
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April 1, 2002
Customer feedback indicates that the Sophias, Psvane Black Treasure and the TJ Music 6SN7s have the sonic attributes of the best of the NOS tubes without the detriments. That's a pretty strong statement, but its been consistent over the last 3 years or so since they started turning up.

So you might look into a pair and see how you like them compared to your KRs.

 

RCA VT231/6SN7WGT, posted on April 15, 2016 at 08:23:34
Lew
Audiophile

Posts: 8778
Location: Bethesda, Maryland
Joined: December 11, 2000
I may have mentioned I found a NOS pair of these in my 6SN7 stash, with the gray smoked glass. They tested as new on my Hickok, whereas only one of my remaining KenRads had not previously seen duty in the MP1, which means I took them out of the MP1 at some time in the past, for some reason, even though they test well. Anyway, I decided to try the RCAs last night. I am very very pleased, especially since these may have been sitting on a shelf for the past 60 or more years. They sound lovely right from the get-go. Bass and midrange to die for. And lack of microphony makes them a bit better than the microphonic KenRads I just removed, which could get shrill on high frequencies. From memory, these sound better than red-base RCA 5692s, of which I have many. I am happy.

 

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