Cryo Treated Tubes

[waassaabee]

I've done a little reading on this and can't figure out if it's mumbo jumbo or not.. A HAM operator friend of mine seems to think it makes sense..
http://www.cryoset.com/catalog/about_us.php?osCsid=158e2deb6ccd1b32d416c75bd86c7ff4
What do YOU think?

 

[Restless Rocks]

Well makes sense but seems to be as much sales pitch as science. I would have to just get a couple and A/B them with some of my vintage goodies to see if there's any real merit to it.

 

[Guitarzan]

I have heard about certain metals that molecularly realign during a cryo treatment. Usually that is done to impove strength. I'm not really sure this would be of any added changes to the tone or longevity of the tubes...

 

[waassaabee]

I have heard about certain metals that molecularly realign during a cryo treatment. Usually that is done to impove strength. I'm not really sure this would be of any added changes to the tone or longevity of the tubes...

Well I'm not sure either, but I bought some just to see waddup..

 

[Russ]

I would be interested in what would happen to NOS or just OS tubes. I wouldn't mind having my Mullards cryo treated if it made a difference. I also have about a dozen GE's and RCA's that I would have done if it made a difference.

 

[ytse_jam]

Well, as a physics student (as far as I know) I can tell you something true is there but I think that more thank likely this treatment would not have any noticeable effect on tone and constructive improvement should be minimal. When decreasing temperature, it is true that a solid material, in order to reaching its energetic balance (it's all a matter of finding the minimum for the Helmholtz free energy), tends to reduce the number of its vacancies (which are atoms missing in certain positions of the crystalline reticulum), so that its micro-structure become more ordered (vacancies tend to be occupied by atoms). Ideally, at the temperature of zero Kelvin (the absolute zero), the solid material shouldn't have vacancies, and if the entropy is exactly zero (no isotopic/spin/vibrational/impurity disorder) we would have the most ordered micro-structure available. But when you re-increase the temperature, atoms will start to move following aleatory motion and there will be the re-creation of about the same number of vacancies as before the treatment, always in order to maintain an energetic balance. And this vacancies re-creation process is more efficient if temperature is increased slowly (as is done with the treatment described in that article). So, the solid material tends to return to its original micro-strutcure (the crystalline reticulum should be slightly more ordered, but not so much)... Instead, if the temperature were increased in a really short time, the micro-structure should maintain its ordered configuration, but I don't know what would happen due to the instable energetic state in which the material would be.

 

[Russ]

Well, as a physics student (as far as I know) I can tell you something true is there but I think that more thank likely this treatment would not have any noticeable effect on tone and constructive improvement should be minimal. When decreasing temperature, it is true that a solid material, in order to reaching its energetic balance (it's all a matter of finding the minimum for the Helmholtz free energy), tends to reduce the number of its vacancies (which are atoms missing in certain positions of the crystalline reticulum), so that its micro-structure become more ordered (vacancies tend to be occupied by atoms). Ideally, at the temperature of zero Kelvin (the absolute zero), the solid material shouldn't have vacancies, and if the entropy is exactly zero (no isotopic/spin/vibrational/impurity disorder) we would have the most ordered micro-structure available. But when you re-increase the temperature, atoms will start to move following aleatory motion and there will be the re-creation of about the same number of vacancies as before the treatment, always in order to maintain an energetic balance. And this vacancies re-creation process is more efficient if temperature is increased slowly (as is done with the treatment described in that article). So, the solid material tends to return to its original micro-strutcure (the crystalline reticulum should be slightly more ordered, but not so much)... Instead, if the temperature were increased in a really short time, the micro-structure should maintain its ordered configuration, but I don't know what would happen due to the instable energetic state in which the material would be.

Wouldn't the glass envelope shatter if brought back from a freezing temperature rapidly? Or would the vacuum inside hold the glass together? I have broken several mugs of mine by even running cool water over them after they have been in the freezer. The glass couldn't handle the thermal expansion rate. I would think the same of a tube. I wouldn't think the vacuum could keep the glass from shattering. I mean if a little shock can break the glass, wouldn't the effects of rapid heating from freezing temperatures also?

 

[ytse_jam]

Well, as a physics student (as far as I know) I can tell you something true is there but I think that more thank likely this treatment would not have any noticeable effect on tone and constructive improvement should be minimal. When decreasing temperature, it is true that a solid material, in order to reaching its energetic balance (it's all a matter of finding the minimum for the Helmholtz free energy), tends to reduce the number of its vacancies (which are atoms missing in certain positions of the crystalline reticulum), so that its micro-structure become more ordered (vacancies tend to be occupied by atoms). Ideally, at the temperature of zero Kelvin (the absolute zero), the solid material shouldn't have vacancies, and if the entropy is exactly zero (no isotopic/spin/vibrational/impurity disorder) we would have the most ordered micro-structure available. But when you re-increase the temperature, atoms will start to move following aleatory motion and there will be the re-creation of about the same number of vacancies as before the treatment, always in order to maintain an energetic balance. And this vacancies re-creation process is more efficient if temperature is increased slowly (as is done with the treatment described in that article). So, the solid material tends to return to its original micro-strutcure (the crystalline reticulum should be slightly more ordered, but not so much)... Instead, if the temperature were increased in a really short time, the micro-structure should maintain its ordered configuration, but I don't know what would happen due to the instable energetic state in which the material would be.

Wouldn't the glass envelope shatter if brought back from a freezing temperature rapidly? Or would the vacuum inside hold the glass together? I have broken several mugs of mine by even running cool water over them after they have been in the freezer. The glass couldn't handle the thermal expansion rate. I would think the same of a tube. I wouldn't think the vacuum could keep the glass from shattering. I mean if a little shock can break the glass, wouldn't the effects of rapid heating from freezing temperatures also?

I think you're right, glass would probably behave as you described. But keep in mind that throwing an object at very high or very low temperature into water at a normal temperature will cause a glass warming/cooling speed of about 100 billions kelvins per second. That's quite a lot (you could not believe at first, but, despite of its semplicity, it is one of the most shocking way to increase/decrease temperature)! Running cool water over a over-heated/under-cooled glass mug is not exactly the same thing but may have a similar impact. The last sentence of my previous post was intended just to show a method to really have (even if just for an instant) a really ordered micro-structure at normal temperature, but obviously it works in ideal conditions. I wanted to stress that re-increasing the temperature slowly would, even if gradually, restore the system's structural disorder.

 

[Russ]

I still think that even though the molecular structure might find better continuity from atoms bonding to reduce vacancies at given temperature, once the particles are reheated to ambient and above any benefit from having been cryo-treated will have been lost. I mean even if you could have your amp on without heating your tubes and have them be warm enough to function (so hypothetical here) but then have them only be hit by pulses from actual sounds created by your guitar, the effects of the cryo-treatment would last what microseconds?

I think the cryo-treatment sales pitch is just that. I think it preys upon people's willingness to want to believe. I would like to see blind studies of people's perceptions of tones heard from both treated and non-treated tubes. Maybe even throw in some really nice NOS stuff and some OS stuff. They could ask someone to donate a nice NOS specimen for treatment for the testing too. If they covered all the variables and actually proved this process as valid without EJ's ears I think I might rethink it.

 

[ytse_jam]

... but then have them only be hit by pulses from actual sounds created by your guitar, the effects of the cryo-treatment would last what microseconds?

The goal is to get a slightly more ordered micro-structure at a normal and/or at working temperature, but not obviously to be in the same conditions as the under-cooled case.

however don't misinterpret me, Russ, what you said is exactly what I think too!

 

[Russ]

Ok so at normal temperature what would the benefit be if the micro-structure changed? Would the steel internals be shinier or something? Would they be more stable? I don't think they make any noise anyway when not at working temperature do they? I don't really care about what they do when they aren't actually working yet. Working temp would be all I would care about. If it made them silent when it is off, I already have that. If it made them have notably decreased noise and microphonics when they are on I would be interested. Sounds like snake oil to me. :wink:

 

[ytse_jam]

Ok so at normal temperature what would the benefit be if the micro-structure changed?

I think it preys upon people's willingness to want to believe.

Good answer!

Well, this is my idea: the presence of a hole in a material is perceived as defective, so people could think that a disordered atomic structure with - for example - a slightly higher number of vacancies is actually a defection, but the truth is that it is not, because the presence of vacancies is part of the inner nature of every material at normal temperature (and they're not macroscopic holes!). Tubes are based on thermionic electrons emission due to the heating of a filament, which is ruled by statistics exactly as the presence and position of the vacancies are.

 

[waassaabee]

I'm feeling the only macroscopic hole here, may be in my head!! :shock:
Thanks for all of the input there gents, I didn't expect quite that caliber of discussion.. I figured it was a bunch of smoke and mirrors, but what the hey.. Nothing ventured, nothing gained.

 

[Guitarzan]

I think you're right, glass would probably behave as you described. But keep in mind that throwing an object at very high or very low temperature into water at a normal temperature will cause a glass warming/cooling speed of about 100 billions kelvins per second. That's quite a lot (you could not believe at first, but, despite of its semplicity, it is one of the most shocking way to increase/decrease temperature)! Running cool water over a over-heated/under-cooled glass mug is not exactly the same thing but may have a similar impact. The last sentence of my previous post was intended just to show a method to really have (even if just for an instant) a really ordered micro-structure at normal temperature, but obviously it works in ideal conditions. I wanted to stress that re-increasing the temperature slowly would, even if gradually, restore the system's structural disorder.

The Delta T would be too much for the glass regardless if Pb xtal, borosilicate crown, BK7... I would buy it if the cryo'd the elements then applied the glass for vacuum.

 

[Russ]

That would make more sense. But even at that, they would have to create the vacuum and seal the tube at incredibly low temps just to have the effectiveness of the process. Last I checked, unless glass is heated to its liquid form you cannot get it to bond with itself. If you don't get a good bond/seal how could anyone expect it hold a vacuum?

 

[ytse_jam]

That would make more sense. But even at that, they would have to create the vacuum and seal the tube at incredibly low temps just to have the effectiveness of the process. Last I checked, unless glass is heated to its liquid form you cannot get it to bond with itself. If you don't get a good bond/seal how could anyone expect it hold a vacuum?

Actually a melted glass can be under-cooled and still maintain a liquid form even at a very low temperature (for a short time), but I think making it bond with itself could be quite difficult in that conditions, and surely it wouldn't be worth if the final aim is to have a tube for a guitar amp for a fair price.
Btw, does anyone know what's the typical vacuum value into a standard tube?

 

[waassaabee]

The Delta T would be too much for the glass regardless if Pb xtal, borosilicate crown, BK7... I would buy it if the cryo'd the elements then applied the glass for vacuum.

Got a pair of cryo treated Svet EL34's and put em in the MkIV last night.. They must have dunked em in some sort of magic joojoo, cause they survived the Delta T, and despite all of the negative speculation, sound pretty damn good! Theory schmeory..

 

[Guitarzan]

I was referring to the glass (^t) coming out of cryo.

 

[Russ]

That would make more sense. But even at that, they would have to create the vacuum and seal the tube at incredibly low temps just to have the effectiveness of the process. Last I checked, unless glass is heated to its liquid form you cannot get it to bond with itself. If you don't get a good bond/seal how could anyone expect it hold a vacuum?

Actually a melted glass can be under-cooled and still maintain a liquid form even at a very low temperature (for a short time), but I think making it bond with itself could be quite difficult in that conditions, and surely it wouldn't be worth if the final aim is to have a tube for a guitar amp for a fair price.
Btw, does anyone know what's the typical vacuum value into a standard tube?

How would you maintain 0K while having to add heat to seal the envelope? I would think any form of bonding would result in the addition of heat thus raising the temp.

 

[Russ]

The Delta T would be too much for the glass regardless if Pb xtal, borosilicate crown, BK7... I would buy it if the cryo'd the elements then applied the glass for vacuum.

Got a pair of cryo treated Svet EL34's and put em in the MkIV last night.. They must have dunked em in some sort of magic joojoo, cause they survived the Delta T, and despite all of the negative speculation, sound pretty damn good! Theory schmeory..

Svetlana EL-34's already sound good. I used to play them in my Marshalls. I can't see them getting any better even if they sprinkled magic fairy dust on them.