[Philistine]

I raised the issue on tube life, it was not my intent to divert the thread - my apologies.

I have tried the following in a Modwright CDP;
Tung Sol 5687 $23
Tung Sol 5687 Cryoed $38
Bendix 6900 $350

The Bendix tubes were superior with the basic Tung Sol's giving 80% of the performance and the cryoed version giving 95% of the performance.  I did a blind test with a friend and he preferred the cryoed tubes, my preference was biased as I knew the tubes being used and more than likely influenced by the cost?
My take from this is that cryoing is a low cost potential improvement option.
Having had a cryoed tube fail (it may have been a one off), and also being a Ceramic Engineer by education, I see the potential of failure when using different materials with different thermal expansion coefficients and bonding agents.
From my limited experience I consider any risk is outweighed significantly by the potential improvements, and would do it again without hesitation.

Robin,
I too have a Butler (3 channel version), love it/great value/underrated.  I'm currently tube rolling in my Modwright Transporter and asked Brendan about cryoing the rectifier tube.  His response was that tubes that were low stressed didn't benefit from the process and wouldn't sell me one, as the Butler's tubes are low stressed then maybe it applies also?   
 

[satfrat]

Robin,
I too have a Butler (3 channel version), love it/great value/underrated.  I'm currently tube rolling in my Modwright Transporter and asked Brendan about cryoing the rectifier tube.  His response was that tubes that were low stressed didn't benefit from the process and wouldn't sell me one, as the Butler's tubes are low stressed then maybe it applies also?   
 

Probably so, heck I have Herbie halo's on mine that that's probably a waste also. I just couldn't see the need o take them out, that's all. But the 3 circuit boards and the transformer I'm sure benefited greatly from being cyroed. Changing the 2 fuses per board (w/audio grade)  wasn't a waste of time either.
 
See Phillistine, we all stray a smidgen.  but the author doesn't seem to mind. 


Cheers,
Robin

[iGrant]

 
See Phillistine, we all stray a smidgen.  but the author doesn't seem to mind. 


Cheers,
Robin

Don't mind at all, it's been a pleasure and education to read the pro's and con's well presented here.

[planet10]

Thanks, I've been told by a few customers that the results are well worth, have actually heard on one of our 300B amps, but it was so heavily modded, it was impossible to tell what I was listening too. Moray James (of Sumo Aria fame) is doing them for me in Calgary, he's been doing it for a while now, if it works out well with the Shuguang tubes, he may be very busy . Says that you can lose some tubes in the process.

As important as the cryo is that the guy doing it knows what he is doing. Moray apprentised under the master so your tubes are in good hands. To get the most out of the process there is more involved than just freezing the tubes. Moray knows these tricks.

My experience with cryo tubes has been positive (all done by the guy that trained Moray).

dave

[jneutron]

1.  While there is a lot of information on cryogenics out there, a lot of it is simply incorrect.  This thread is no exception, unfortunately...caveat emptor.
2.  The specific transformation I mentioned is a Diffusionless transformation.  In other words, nothing within the material has to move through the lattice to effect the transformation.  I provided a reference which discusses the change from a Face Centered cubic crystal structure, to a Body Centered Crystal.  It requires NO diffusion, or transport, of atoms through the material to affect the change.  This is unlike a silver or gold plate over copper, where the metal will indeed diffuse into the copper.
3.  The alloy I speak of freezes in a specific lattice pattern, FCC, and leaves within the lattice, Potential energy..not excess kinetic energy, that is a silly description....POTENTIAL energy.  The verbage "excess kinetic in the material" comes from one who does not understand physics very well.  Either the source is uninformed, there was a translation error, or a marketing person massaged correct information into what is written.  Proofreading would have helped here.
4.  Glue is NOT used as a hermetic seal for vacuum tubes.  They are not capable of preventing molecular diffusion of gases.  The seals are actual atomic bonding of the glass of the envelope to the metal of the leads. Note:  Sometimes, it is not an atomic bonding process at all, but just very very intimate contact like a compression seal.
5.  While the FCC to BCC transformation does indeed alter the density, that change will not be measureable outside of the NBS lab.  Nor, will the conductivity change be measureable, as current technology  meters that can be purchased are only capable of 1 part in 10 to the 10th resolution.Note:  this also requires the material being measured be temperature stable and measured to accuracies in the millikelvin range.  Trust me, that is not very easy.
6.  Grain boundary interactions (and cryo annealing to alter such) with electrons remain UNMEASURABLE using current technology at room temperature...it's in the numbers also.  The difference can indeed be measured at liquid helium temperatures, as the dislocations will affect the mean free path of collisions between the electrons and the lattice structure.  At 4.5 Kelvin, a very good copper will exhibit three orders of magnitude BETTER conduction than it does at room temperature, mean free path being 4 to 10 cm, as opposed to hundreds of nanometers.

Alan:  While I do not concur with the audio benefits of cry treatment, I also cannot discount it.  I have not used cryo on audio components, "just other stuff".   Other than that earlier sentence I had ta tweak ya with , everything you are saying w/r to cryo processing I find refreshingly accurate.

I would mention one finer point:  Many insulators are capable of surviving a well controlled cryo treatment, but be careful that the wire is not bent too tightly.  If a wire is too tightly bent, the insulation may crack at the bend.  This is VERY important for hv and AC lines, as they can hit chassis.

Cheers, John

[opaqueice]

5.  While the FCC to BCC transformation does indeed alter the density, that change will not be measureable outside of the NBS lab.  Nor, will the conductivity change be measureable, as current technology  meters that can be purchased are only capable of 1 part in 10 to the 10th resolution.Note:  this also requires the material being measured be temperature stable and measured to accuracies in the millikelvin range.  Trust me, that is not very easy.
6.  Grain boundary interactions (and cryo annealing to alter such) with electrons remain UNMEASURABLE using current technology at room temperature...it's in the numbers also.  The difference can indeed be measured at liquid helium temperatures, as the dislocations will affect the mean free path of collisions between the electrons and the lattice structure.  At 4.5 Kelvin, a very good copper will exhibit three orders of magnitude BETTER conduction than it does at room temperature, mean free path being 4 to 10 cm, as opposed to hundreds of nanometers.

I looked around on the web a little, and it does seem that cryo treatments are used to treat steel tools.  Since there appear to be tangible benefits to that, the treatment must significantly alter the macroscopic physical properties of steel in some significant way, no?

By the way, when I said the resistance change should be easy to measure, I was responding to a comment which proposed it might be such a change that was responsible for audible effects.  So I repeat - IF there is an audible effect from cryo treatment AND it's because of a change in the resistivity of the metal, that ought to be easy to measure.

[Imperial]

I do mention some stuff about generic cryo treatment in this here thread. Recommended reading!
(This is a generic info... It's basic metallurgy.)
It does indeed shed some light on the matter...

Imperial

[jneutron]

I looked around on the web a little, and it does seem that cryo treatments are used to treat steel tools.

Yes, it is used for a wide range of applications to improve some specific attributes.  Brake pads, musical instruments (brass), etc.

Since there appear to be tangible benefits to that, the treatment must significantly alter the macroscopic physical properties of steel in some significant way, no?

Yes, it does alter the macro properties by micro  changes to the structure.

By the way, when I said the resistance change should be easy to measure, I was responding to a comment which proposed it might be such a change that was responsible for audible effects.  So I repeat - IF there is an audible effect from cryo treatment AND it's because of a change in the resistivity of the metal, that ought to be easy to measure.

I did not intend to present your comment as incorrect, I agree with your statement...  Sorry for the confusion.

What is a more important question is..  why is it the anecdotal accounts are always improvement as a result of cryo, as opposed to a 50-50  or gaussian distribution of change?

Cheers, John

[Imperial]

Indeed a good question... I have an answer to that.
If the parts of an amplifier circuit is made more "stable"...
The music will most likely not suffer.

Imperial

[jneutron]

Indeed a good question... I have an answer to that.
If the parts of an amplifier circuit is made more "stable"...
The music will most likely not suffer.

Imperial

Unfortunately, you have not answered the question.

Why is it assumed that the system stability is IMPROVED by a technique which provides no measureable change..without regard to the type of system??

Why is it assumed that the process even changed the system stability?  Nevermind, ALWAYS causing a change that improves the system, never makes it worse??

Implicit in your remark, is that there is a basic physical understanding of how the process changes some "entity" which is bad before the process..but yet there is no smoking gun, is there?  No indicators of any change in density, resistivity, capacitance, inductance, permeability, permittivity, dielectri absorbtion, frequency or amplitude response..  None of the physical attributes that are used to actually design the system, none of the system response changes..

The general attitude is that cryoing is GOOD, that everything subjected to the process will come out better.

And why is that???

The answer:  because in the real world, cryo processing is only used where it works to improve the product in some way.  How many car manufacturers cryo a critical safety component because experience showed them that the part is heavily damaged by the process???    None..  It's only used when there is a benefit, not a detriment.

Audio cryo so far.. falls into the "can't prove it works by any measurement currently used" category.

And....not everything that is cryo processed is better as a result..again, it is a gaussian distribution.


Cheers, John

ps.  and I am very well aware (perhaps moreso than most) that current measurement techniques are incapable of measuring any process which impacts localization of a soundstage.  The bulk of the audio scientific types currently out there do not even understand the issue.

[alan m. kafton]

Excellent analysis as usual, john.

And....not everything that is cryo processed is better as a result.

It is important to mention that some have experienced a detriment to a few products that underwent cryo treatment, such as cabling. Mostly, they "didn't like how it sounded" after the treatment. This can be explained by a few factors....1) the resulting sonics are a purely a matter of personal preference, 2) there was no "control" as to the cryo treatment used, i.e., the differing processes utilized by different companies (there *is* a difference), and 3) the products were not re-conditioned fully to sound their best. Previously used cables, for instance, retrograde as a result of cryogenic treatment, and require a number of hours of re-conditioning (break-in, burn-in, etc.) to sound their best. Here again that information (whether the cable in question has been given enough time) is usually not mentioned or disclosed.

In one case I'm aware of, a customer I know had all of his cables cryo-treated (independently of me), and some of them (a rather exotic design) were "ruined", in his words. Well, the adhesives used in these particular cables failed, and the mechanical damping materials (sand-like material) spilled out of the cable jackets. They were returned to the manufacturer for repair. An ounce of caution might have saved them, if the customer would have made inquiry (to the manufacturer) about the cables in the first place. He blindly assumed that all would be well. I always tell customers, as does Charles at CI, "when in doubt, call the manufacturer". If the manufacturer has no experience with cryo treatment, then the customer is taking a chance on that particular design. Please note that the overwhelming majority of cables do just fine with cryo treatment....but a few designs should require some inquiry, of both the manufacturer and treatment facility. It is a matter of both experience, and caution.

[iGrant]

The general attitude is that cryoing is GOOD, that everything subjected to the process will come out better.

And why is that???

Very good point John. Part of any 'ear' testing I do is to swap back a week later (which I also suggest to anyone who listens to me and see if the perceived difference is actually better to my ears. Me thinks it's human wishfull thinking that any difference must be better sounding.

[jules]

John/jneutron,

thanks for setting things straight on several matters. The quote from Dr. Trucks referring to kinetic energy came from this site ...

http://www.cryogenicsinternational.com/posfdbk.htm

referred to earlier in this thread as a useful source of information on cryo treatment

I have no idea which of your explanations explains how this piece of nonsense managed to find a place on the website of a cryogenics business but it does give the process a bad name when an "expert" apparently comes out with bilge.

There hasn't been any feedback here on the tin allotrope issue though I believe it could have potential [not kinetic] significance. Would it be possible to do a trial on this? I'd suggest subjecting a nice shiny blob of tin solder to a treatment and then closely examining it. If the surface shows any powdering it would not be a good sign. This powdery finish would not be an oxide, it would be a different form of tin in the same way diamond is a different form of carbon and it would not just be superficial.

jules

[jneutron]

John/jneutron,

thanks for setting things straight on several matters. The quote from Dr. Trucks referring to kinetic energy came from this site ...

http://www.cryogenicsinternational.com/posfdbk.htm

referred to earlier in this thread as a useful source of information on cryo treatment

I have no idea which of your explanations explains how this piece of nonsense managed to find a place on the website of a cryogenics business but it does give the process a bad name when an "expert" apparently comes out with bilge.

Agreed

There hasn't been any feedback here on the tin allotrope issue though I believe it could have potential [not kinetic] significance. Would it be possible to do a trial on this? I'd suggest subjecting a nice shiny blob of tin solder to a treatment and then closely examining it. If the surface shows any powdering it would not be a good sign. This powdery finish would not be an oxide, it would be a different form of tin in the same way diamond is a different form of carbon and it would not just be superficial.
jules

I've purchased and used about 2 tons of tin/silver solder (96/4) so far.  Most of it was bar stock, used in multiple solder pots.  About 400 pounds was in the form of rosin core, in .125, .062, and .031 inch diameters.  And a coupla hundred pounds in ribbon form, soldered in an induction setup to run the 10 meter long overlap splices.

The solder joints run the gamut from #32 awg wire to wire, to 8 inch long half inch wide overlap splices that carries 7,000 amps, to the 10 meter long joints which support superconductors...

Every solder joint using that tin/silver alloy (guesstimating about 100,000 joints), is operating in liquid helium.

There has been NO tin pest.  Ever.  It's been 14 years now, and there has not been a solder joint failure.

It is believed that the lead in lead-tin prevents the pest (as well as whiskers), and some also believe the same applies to the silver in the eutectic mix. (the jury is still out on that however)

I wouldn't worry about either solder type with pest.  I do however, worry about the component leads that we purchase, they are pure tin plated (well, at lest 2/3rds of all the components manufactured today).  It isn't possible to swamp the pure tin all the way to the plastic bodies, I see planes fallin from the sky in the future..or at least, cell phones that die after two years from whiskers or pest.

Swatch got a exception to ROHS lead...

Cheers, John
ps.  The machine at CERN, they will use far more tin/silver, and they go to 1.88 Kelvin, superfluid helium.  Colder..

[Imperial]

  So many words here, it is amazing!
Understanding when to cryo and when not to cryo is important.

Cryogenics has not been around for 20 years, they started to use this method in the 1870's...
That's more like 120 years ago.. (in about the 1960's they started to use "tempering" by cryo..)

As to measuring, that is the easiest thing in the world!!!

Take two small bells, make sure that they are exactly the same in pitch, Cryo treat one of them...
And "Ding ding" the one that was cryoed will have a pitch that now is slightly lower...
Try using an analyzer and test... it will have a lower sound to it...
Just an example of things you can measure... after cryo treatment..
Say a glass envelope is like a bell out of glass now isn't it... And it goes on...

Imperial

[opaqueice]

Take two small bells, make sure that they are exactly the same in pitch, Cryo treat one of them...
And "Ding ding" the one that was cryoed will have a pitch that now is slightly lower...
Try using an analyzer and test... it will have a lower sound to it...

What do you think of this?

http://www.acoustics.org/press/146th/jones.htm

[jules]

 

bells are perverse and produce a mixture of all sorts of strange harmonics but Imperial's example is not inconsistent with the info so far.

There's been some very informative input into this thread and I don't see too many contradictions amongst the best of it.

The trumpet study seemed to be very inconclusive though interesting.

Thanks again John ... two tons of tin solder immersed in liquid helium is more than enough evidence 

jules

[jneutron]

So many words here, it is amazing!
Understanding when to cryo and when not to cryo is important.

Cryogenics has not been around for 20 years, they started to use this method in the 1870's...
That's more like 120 years ago.. (in about the 1960's they started to use "tempering" by cryo..)

As to measuring, that is the easiest thing in the world!!!

Take two small bells, make sure that they are exactly the same in pitch, Cryo treat one of them...
And "Ding ding" the one that was cryoed will have a pitch that now is slightly lower...
Try using an analyzer and test... it will have a lower sound to it...
Just an example of things you can measure... after cryo treatment..
Say a glass envelope is like a bell out of glass now isn't it... And it goes on...

Imperial

A bell is not a glass envelope.

A change in the resonance frequency of a bell, does not mean a glass tube will undergo the same "transformation".

A change in the toughness of steel as a result of excursion below the martensite finish temperature does not mean that all metals will do the same.

The fracturing of some insulations subjected to cryo does not mean all insulations will suffer the same fate.

The survival of Emerson and Cuming 2850 ft with hardener 24 through hundreds of thermal cycle dips in liquid helium, does not mean all epoxies will survive.

Are you seeing a trend here yet?  You are attempting to make blanket assertions, attempting to present the argument that ALL materials will change their resonance frequency, all will change for the "good"...  It pays no-one to make such sweeping and unfounded statements.

A change in the envelope resonance, if it occurs, is of no concern if the resonance of the envelope does nothing to the circuitry.  What would be of concern is :

1.  The Q of the envelope.  If damping lowered, Q will go up.  And microphonics will indeed rear their ugly head even more.
2.  The fundamental frequency of resonance, if it can excite the internal elements to vibrate at one of their modes.

If changes to the envelope was of any concern, it would be better addressed with tube dampers, and isolation techniques.  Dropping a tube into LN2 without regard to any physics or engineering is like tossing excrement on a wall and hoping some sticks.  It does nothing for SOTA.

Have YOU tried to measure a change in the envelope characteristics?  Data such as that would be of real interest.  Blanket assertions don't float my boat, as there is no record of applicability yet.

But it would be an excellent test on it's own..perhaps you should follow up on the assertion..



Why is it important to establish a starting date for cryo?  Did someone post something to the contrary?

Soldering's been around for two thousand years.   And yet, I still see lots of garbage on the web.  Cryo is the exact same boat.


Cheers, John

[Imperial]

Well, While reading the thread some stuff stood out, so I did some answers.
I do not think I'm right on all accounts. Nor do I think the angle I describe is the only one..
But as you point out, some part will not respond well to cryo treatment... the link in my first post in this
thread does take up some of that..

However, I'm not here to talk, as I feel is the case with us all here now.
I'm here to share my opinion, not defend it. Sort of like post - Annealing or Cryo as we know it by..
It's a given many people will not agree with some ways of this , or even disagree very hard!

I've not tried cryo treatment as a "stress release" in heated arguments.. but I'm sure that just won't be
nearly as cool as it sounds.. 


Imperial

[satfrat]

Well thanks to this thread getting me reaquainted with the positive benefits I've received, I today sent out my Trends UD-10.1 USB transport and accompanying Channel Island VDC-SB power supply to Charles Beresford of Cryogenics International. Should be an 8 day turnaround and considering computer audio is my sole audio source, I'm once again anxiously awaiting next wednesday. 

Price, $100 plus $66 Fed-Ex Espress 2 day shipping both ways. (I just know someone will ask so,,,) 


Cheers,
Robin