Cryogenics

Quiet Earth · « **Reply #20 on:** 3 Jul 2012, 08:36 pm »

Not sure if the skeptic thing was directed at me but I do want to point out that :

1. The thread is about cryo tubes, not baseball bats or rocket ships.
2. I bought and used 6 professionally cryo'd audio tubes.
3. Two of the tubes died right away and the other four gradually turned to crap.
4. When I have direct user experience with something then I feel like I can say whether or not I like something.
5. I know that I don't understand the ins and outs of cryo, and I do not dismiss it altogether. I know that it just didn't work for me and it's possible that it was the tubes and not the cryo process.

SteveFord · « **Reply #21 on:** 3 Jul 2012, 09:34 pm »

Oh, yeah? Your mother wears Army boots and she dresses you funny, too.

That wasn't directed at anyone, I just wanted to get any fighting out of the way.
It looks like there's no concensus (just like with anything else in audio) so I'm going to have to perform an experiment.
The one tube the wife and I can really tell the difference in is the 6SN7 in the deHavilland preamp.
Here's the plan:
1) get two NOS RCAs and have them tested
2) listen to both (they should sound identical) and send one out for the Walt Disney treatment
3) listen for any sonic differences for a short period of time
4) insert the cryo'd one for 100 hours, pull it out and insert the regular tube for an equal amount of time
5) compare the sonic differences (if any)
6) have both tubes retested.

Would 100 hours be long enough and is there one cryo shop that is really the one to use above all others? I had PI Audio recommended as a good one.

Quiet Earth · « **Reply #22 on:** 3 Jul 2012, 10:00 pm »

I would run the tubes for at least a month or two before making any long term judgement calls but you can at least get a good idea in 100 hours.

I'll let the other more knowledgeable guys tell you where to send the tubes.

Mom never was very color coordinated, especially when she had those damn boots on.

. (just kidding mom

)

simoon · « **Reply #23 on:** 3 Jul 2012, 10:21 pm »

Quote from: JohnR on 2 Jul 2012, 02:04 pm

Thing is - tubes get hot. Doesn't this "undo" whatever cryo treatment does?

No.

The cryo process changes the molecular makeup of the metal. Warming the metal up again does not undue the change.

JakeJ · « **Reply #24 on:** 3 Jul 2012, 11:00 pm »

Steve,

I think you have a good basic plan there and am looking forward to a posting of your experience. I cannot make any recs as to who to have your tube cryo treated by but maybe jtwrace can help there as he has had good experiences. It does seem, through my readings, that slow ramp times are important. Judging from what Quiet Earth mentioned about his experience with Cryoset tubes specifically may be indicative of a poorly chosen cryo process. Maybe do a search on cryo treatment here on AC and see if you can come up with a short list of members to contact via PM to ask for advise.

It would also be cool if our AC tube gear manufacturers could pipe up with any opinions they might have formed.

mjosef · « **Reply #25 on:** 4 Jul 2012, 12:18 am »

I have a few pairs of tubes (cryoed) from Cryoset, TS 12AX7 (reissue), TS 12AU7 (reissue), Sovtek 12AX7LPS...I compared the TS-AX7's and Sovtek LPS, to non cryoed versions, and much preferred the cyroed versions.. the cryoed tubes sounded 'sweeter' and more extended with a notable better 3D presentation.
The TS -AX7's has been in use for over a year , the LPS and AU7's has been in use for only 3 months and so far no problems.

Since the cost via Cryoset is about the same from non cyroed vendors, its easy enough to experiment for oneself whether a cryoed tube offers any benefit over a non-cryoed one.

YMWV.

SteveFord · « **Reply #26 on:** 4 Jul 2012, 02:01 am »

I wrote to Cryoset to see if they'll do their treatment to a supplied tube.
They do offer the RCAs I like but only in pairs and what I want is one cryo'd tube and one regular.
I realise that my experiment won't be statistically valid due to it's miniscule scope but it will satisfy my curiosity if nothing else.

Ericus Rex · « **Reply #27 on:** 4 Jul 2012, 10:41 am »

Scott F. Thanks for all the info. Very informative. I did some perusing on the 'net last night. I can't find any info on the change to the metal's conductive properties after treatment. Those links you show talk only of improved wear resistance which would be great for tools but pointless for tubes, I would think.

All the links I checked also mentioned a required tempering after treatment of 300-450 deg C to get maximum effect. Does anyone know if the cryo companies are doing this tempering to tubes? Also, which metal in the tube is the cryo process optimized for? The tungsten cathode? or the nickel plate? Does it matter?

I also see no info anywhere on what happens to the cryo effect in the metal at higher temps. Anyone know what happens to the metals if the original tempering temp of 300-450C is exceeded? Simoon, the fact that the process requires tempering implies that the changes to the molecular structure are actually not permanent.

Until I see more info on high heat applications I'm still a skeptic of the benefits of this process in tubes. Thanks for the good info everyone!

Scott F. · « **Reply #28 on:** 4 Jul 2012, 12:11 pm »

Ericus,

Glad you read the links

Read this link too. This one is on quantum tunneling. It is the effect that electrons have when travelling through a conductive material.

http://www.jandrpc.com/Quantum%20Tunnel%20of%20Love.htm

I realize that the concept behind this paper is quite controversial to some, taken with the cryo links, specifically speaking to what an electron has to to 'tunnel' through a grain boundary (essentially impurities), the two papers are very relatable and could explain why some hear the difference.

On the wear side, the cryo links described a dramatic reduction of micro-cracks and stress relieving of the metals treated, providing uniform stresses across the structure. This should relate directly to increased tube life. How long...who knows.

I find it interesting and completely plausible that QEs experience with prematurely loosing tubes that have been cryoed. That makes sense. If you have tubes that didn't test well or had significant micro-cracking in the filament [say, where they bend around the grid], I could see the cryo process causing too much stress and leading to a premature death. The other reason might have been if the tubes weren't cryoed properly (thermal shock) but one never really knows. Heck, could have just been bad luck, we all experience that from time to time.

Now, the Quantum Tunneling paper tries to give credence to the sonic effects of 'break in'. Our community is split on this issue and that's fine, no need to revisit it hear but the essential 'hardening' of the materials, reduction of the grain size and elimination of boundaries, you would think that there might be a difference in the way that treated material might sound.

Let me try a food analogy. Think of the effects that cryotreatment has similar to what a food processor does to mixed veggies. The metals we all use come from the processor on the 'chop' setting. When you cryo something, it is like using the 'puree' setting. In turn, the end product(s) don't really taste the same, or you might conclude after reading the analysis....or not and that's OK too.

Whether you hear the differences is obviously up for debate. All I can say is try it. It's a cheap tweak that may just add the final touch to your system.

SteveFord · « **Reply #29 on:** 7 Jul 2012, 04:49 pm »

My slow motion experiment is under way.

I had two orange lettering RCA 6SN7 tubes tested this morning and both tested pretty close to being the same (one was 100, one was 96 on the Eico tester) so I fired one off to cryoset for them to do their thing.

While I was at Harrisburg Radio Labs I also dropped off that Sherwood S2000-II tuner for a check up and alignment. That one is a gift for my wife who could care less but I'll get to listen to it so I'm excited.

kevin360 · « **Reply #30 on:** 8 Jul 2012, 07:47 pm »

Quote from: simoon on 3 Jul 2012, 10:21 pm

No.

The cryo process changes the molecular makeup of the metal. Warming the metal up again does not undue the change.

So, how does that affect thoriated tungsten and oxide-coated emitters?

The material layering is crucial for the behavior of the tubes. What impact does the deep freeze have on the interaction between those layers? Optimizing work function and producing a longer lasting sharp edge aren't exactly the same things.

I know very little, but I see reasons to be skeptical. I can't get past a suspicion that the cryogenic process could well be destructive. Some of these comments support that suspicion.

---

Steve, that will have to be quite a long experiment. You'll have to run each tube for a while before attempting a comparison. I'm looking forward to reading your results.

SteveFord · « **Reply #31 on:** 8 Jul 2012, 09:38 pm »

Heck, I don't have to run the tube that I'm going to use for a comparison as I use that one every day.
This might give you a laugh:
When I tested the tubes at Harrisburg Radio Labs we did the one that I sent out for the deep freeze and then I said, "And now for my Secret Weapon".
The repair guy laughed and went, "Secret Weapon, huh?" and we plugged it in and the needle went Boiiiiiiiiiiiiiiiiiiiiipppppppppp! up to 100 and he goes, "I've never seen a tube test that high before!" and I told him, "That's why I call it my Secret Weapon!".
They both sound just about the identical but if the cryo'd tube sounds better than my Secret Weapon I'll be a believer.
I didn't want to send out my Secret Weapon tube because if it fails for whatever reason that would really suck.

Ericus Rex · « **Reply #32 on:** 9 Jul 2012, 12:43 am »

I'm more interested in how different (or similar) they sound after 100 hours. As I said before, I suspect that the cryo'd tube will begin to lose it's 'new' sound after some hours of use. I will patiently wait your results.

SteveFord · « **Reply #33 on:** 24 Jul 2012, 12:24 am »

Well I'll be dipped in liquid nitrogen.
The cryo'd orange lettered RCA came back from Cryoset today so I let my secret weapon RCA warm up during dinner and then put Zappa's Apostrophe' on the turntable to give it a spin.
It sounded good as always so I shut the preamp off and put in the one from Cryoset and gave that a brief warm up.
Here is my take on it: there is an improvement in detail and depth - it's not night and day as it sounded pretty good before but it IS there.
I hear a bit more of the numerous backround vocals and the high end is increased as well. The soundstage is deeper, too.
I put on Revolver by the Beatles and it struck me that the best way to describe the difference is that the sound "tightened up" which I believe is what happens to the treated part.
This link I just found put it a bit more eloquently
http://www.metal-wear.com/Theory.html
but I think that explains what I mean by "tightened up" or as my wife put it, "it sounds clear" but she says that she didn't hear a difference.
She was also sitting off-axis and not really paying attention, either.
I had 26 tubes going at the time (amps, phono stage, preamp) and only had the one tube done that makes the most readily discernable difference and the one I can get at the easiest: the 6SN7 tube in the preamp.
I would say that the difference in doing that one tube is like going from a good interconnect to a really good interconnect. It won't make your jaw drop BUT you'll hear a bit more of what's on the album.
I also must note that I didn't send him my best tube just in case something would go amiss either in transit or in use.
The cryo'd tube is now the best tube.
It's now late July and those are my initial impressions, we'll see how it goes in a month or two from now.

On another note, Ron Sheldon at Cryoset has been great to deal with - real good communication and instant service, too.
I was worried that things would take forever but that's not the case.

thunderbrick · « **Reply #34 on:** 24 Jul 2012, 01:52 am »

Based on Steve's excellent test results, I'm going to have all my tubes cyro'd!

Coincidentally when hell freezes over.

SteveFord · « **Reply #35 on:** 24 Jul 2012, 02:35 am »

Your speakers are certainly good enough to show up anything so maybe pick up some spare tubes, send them in and judge for yourself.
That's what I did as the whole thing seemed kind of strange to me but I'm always willing to be surprised.

thunderbrick · « **Reply #36 on:** 24 Jul 2012, 03:16 am »

Just yanking your chain, Steve!

Added a Forte #3 amp to biamp the Maggies, tweaked the crossover, and these things are really SINGING! It's taking a long time but each change helps. In some cases a LOT!

So, do I stick my tubes in the freezer? Right next to the damned bird?

SteveFord · « **Reply #37 on:** 24 Jul 2012, 09:28 pm »

If it's good enough for Walt Disney, it's good enough for Jenny.
There's something to this Cryogenics bit and I'm told that the sound will change a bit over the next week or so - less "tizzy" on the highs, for one. I know that Zappa's voice seemed to be a bit more forward (or pronounced) than it was with my secret weapon tube.
I think the recommendation for this particular vendor was a good one as it's like anything else - there's so many ways to do things but not all of them might be the way to go. It looks like it's more than just plunk it in the soup and set the dial to Really, Really Cold.
What got me thinking about this was that Cheap and Cheerful thread about what's the biggest rip off in high end audio.
I first thought cryogenically treated anything but then I realized that I had no first hand experience so there you have it.

JakeJ · « **Reply #38 on:** 25 Jul 2012, 04:03 am »

Steve,

Thanks so much for conducting this experiment and reporting back with your findings. Hope you'll give us one more report in a week or so and do a direct comparison to your "secret weapon" tube at that time. One thing you haven't mentioned (or maybe my question is answered on the Cryoset website) is what the cryo treatment cost you?

Jake

SteveFord · « **Reply #39 on:** 26 Jul 2012, 10:10 pm »

I haven't had a chance to do much listening as my computer is dead and the wife has been downstairs and she likes her flat screen so...
For pricing, Ron from Cryogenics states:

I charge $7.50 per tube + $5.00 return postage. I can offer $5.50 per tube in batches of 25+, all shipping to a single address and no shipping charge

My better half is in NYC this weekend so I hope to listen a bit more and report back.