Cryogenic treatment of power outlets - recommended or not?

[spiritofmusic]

Hi fellow What'sBesters. I've arrived at my final solution for power concerns. Consigned my Burmester conditioner out of the system, and alongside already-installed Entreq Silver Tellus/Apollo grounding, I'm going to be powering my rig via, in sequence: dedicated consumer unit>ring main>dedicated unswitched socket>8K Westwick 8kVA balanced power transformer>equipment.
I was initially going to run off the transformer: 5-10 separate Oyaide runs into dedicated Furutech Rhodium plated sockets. But due to a combination of cost and complexity reasons (incl the possibility of introducing ground loops/hum with so many runs, and my losing battle to find an electrician who is confident to get install right AND w/out charging me a small fortune), I'm now going to specify the Westwick to have 10 sockets hard wired into the transformer chassis so I can plug components direct into the box (v. much like a rack mounted conditioner).
My qs are: if I have an option to go Rhodium plated on the socket outlets, should I? I'm aware this presents a slightly "cooler" presentation than Gold, and in the context of my system likes, I'm confident this will be for the best. But I'm open to being convinced to go for Gold, or no special plating.
BUT... most vitally, should I go for cryogenic treatment of the sockets? I'm really all at sea re this decision, and would be grateful for the pros and cons.
I know quite a few tube guys are actually railling against cryo'ing their glowing bottles, and wonder if this is a consideration for hard wired mains products such as sockets/transformers.
I need to make my decision in the next few days, so immediate opinions I'm grateful for in advance.

 

[Speedskater]

It's a bad idea!
There is a poster on some pro-audio & hi-fi forum's. His day job is as an E.E. at a major research lab designing and installing 150,000 miles (yes, miles) of wire and cable (much of it for super conductors). He writes.

When a plastic is subjected to cryo, several things can happen, few of them good.

1. Internal stresses of a machined or molded plastic part can be "relieved" during cryo by internal differential contraction, base contraction around metals, or simple failure at a stress concentration. The vendors do not have the ability to see this at the microscopic level, the casual user certainly cannot. Any plastic part which by design, is supposed to dielectrically isolate two parts, like hot to ground, hot to neutral, and has been structurally compromised by cryogenic temperatures, is a bad thing.

Any feature in a piece of plastic which has been molded in or machined in, incurs the possibility that there are stresses within that will not enjoy cryo.

2. Plastics shrink in the 100+ PPM/degree C range, whereas copper is 16, steel is 12, aluminum is 25. Any metal part inside a slot or opening of a plastic part designed to constrain it physically, will shrink far less than the plastic surrounding it. The metal will not give in this case, but the plastic will. At the temperatures where the forces will be the highest, the plastics are brittle and non flexible.

3. Wire insulation becomes brittle cold. The purpose of the bending radii limitation in the NEC is to prevent insulation degradation over time...if you have an overly tight bend in a wire, the insulation on the outside of the bend is in high tension, the inner is in high compression and typically buckles. Any insulated wire which is exposed to cryo has to, by design, have a defined bending radii considerably larger than code for room temp, as the stressed insulation will crack.

The most dangerous aspect of cryoing parts which have NOT been designed to maintain integrity through the process is that of the failures which are not spotted.

I maintain that there are very vary few (if any) audio vendors out there who have the expertise to know what to look for and where to look for it... to guarantee that what was done to the part did not compromise it's safety.

Polyimide (kapton) is the best plastic for cryo survival as it retains flexibility even in liquid helium. However, it is NOT self extinguishing should an arc develop. It was for that reason that it is banned in all military flight hardware (and should never be used in the home for any wiring). Tefzel is not as good, but is more abrasion resistant and retains some flexibility past liquid nitrogen temperatures.

But honestly, cryogenic treatment does not alter the room temperature current carrying properties of a normal metal, but can alter the physical properties a tad.

 

[spiritofmusic]

S'skater, what a wonderfully informative reply, thank you. Moving away from this option as fast as I can, ahem, skate!

 

[Lee]

It's a bad idea!
There is a poster on some pro-audio & hi-fi forum's. His day job is as an E.E. at a major research lab designing and installing 150,000 miles (yes, miles) of wire and cable (much of it for super conductors). He writes.

When a plastic is subjected to cryo, several things can happen, few of them good.

1. Internal stresses of a machined or molded plastic part can be "relieved" during cryo by internal differential contraction, base contraction around metals, or simple failure at a stress concentration. The vendors do not have the ability to see this at the microscopic level, the casual user certainly cannot. Any plastic part which by design, is supposed to dielectrically isolate two parts, like hot to ground, hot to neutral, and has been structurally compromised by cryogenic temperatures, is a bad thing.

Any feature in a piece of plastic which has been molded in or machined in, incurs the possibility that there are stresses within that will not enjoy cryo.

2. Plastics shrink in the 100+ PPM/degree C range, whereas copper is 16, steel is 12, aluminum is 25. Any metal part inside a slot or opening of a plastic part designed to constrain it physically, will shrink far less than the plastic surrounding it. The metal will not give in this case, but the plastic will. At the temperatures where the forces will be the highest, the plastics are brittle and non flexible.

3. Wire insulation becomes brittle cold. The purpose of the bending radii limitation in the NEC is to prevent insulation degradation over time...if you have an overly tight bend in a wire, the insulation on the outside of the bend is in high tension, the inner is in high compression and typically buckles. Any insulated wire which is exposed to cryo has to, by design, have a defined bending radii considerably larger than code for room temp, as the stressed insulation will crack.

The most dangerous aspect of cryoing parts which have NOT been designed to maintain integrity through the process is that of the failures which are not spotted.

I maintain that there are very vary few (if any) audio vendors out there who have the expertise to know what to look for and where to look for it... to guarantee that what was done to the part did not compromise it's safety.

Polyimide (kapton) is the best plastic for cryo survival as it retains flexibility even in liquid helium. However, it is NOT self extinguishing should an arc develop. It was for that reason that it is banned in all military flight hardware (and should never be used in the home for any wiring). Tefzel is not as good, but is more abrasion resistant and retains some flexibility past liquid nitrogen temperatures.

But honestly, cryogenic treatment does not alter the room temperature current carrying properties of a normal metal, but can alter the physical properties a tad.

My experience has been different. All the best performing outlets I have tried have been cryo'ed.

 

[CGabriel]

I posted this on another forum but it is relevant to this thread. I have paraphrased the question and removed the OPs avatar name.


Originally Posted by xxxxx
Caelin, would you recommend gold or rhodium plated AC contacts?


We have manufactured our own connectors, exclusivesly for our power products, for about ten years. In that time we have experimented with many different types of base metals and surface platings. At one time we had plugs and sockets that had silver, gold, and rhodium platings. The best of those, sound quality wise, were the pure silver plated, brass contacts.

Then, we developed a proprietary cryogenic treatment. When unplated contacts, pure brass, where treated with this process they outperformed all the various plated contacts. So we dropped all of the platings for our connectors. However we continued our research for better performing connectors and outlets.

We recognized that the absolute best contact for sound quality was pure copper. But pure copper thas many technical problems when used as a comtact. First is corrosion and the second is that copper is soft and doesn't have the spring strength required for AC contacts. Eventually we found that Tellurium copper had the necessary strength. Although we don't advocate platings it was required to protect the copper. After many tests we found that a thin layer of nickel performed best due to the fact that it has the lowest Galvani potential.

To answer your question, we prefer no platings when possible. If platings are needed for corrosion protection we prefer a single layer of nickel. What most people do not understand is that all gold, silver and rhodium plated contacts are first sub-plated with nickel. So there are multiple layers of different metals.

Plated contacts each add a different sonic coloration depending upon the type of plating and the base metal. For base metals I prefer copper or a copper alloy such as brass. When brass is the contact base metal I prefer no platings if the metal is cryo treated. For copper base metals i prefer a single layer of nickel. I believe that (not sure) Furutech is developing connectors with copper base metals similar to our CopperCONN connectors. If that is available, that is what I would choose whatever the plating material might be. Otherwise, ask for no platings or a simple nickel plate. If you twist my arm and say that I can only choose between gold and rhodium plating I would choose gold plating. You may prefer something elese depending upon system balance.

 

[Phelonious Ponk]

It doesn't really do much good to cryo the outlets if the Romex in the walls is left undone. Gotta freeze the whole house.

Tim

 

[MylesBAstor]

It's a bad idea!
There is a poster on some pro-audio & hi-fi forum's. His day job is as an E.E. at a major research lab designing and installing 150,000 miles (yes, miles) of wire and cable (much of it for super conductors). He writes.

When a plastic is subjected to cryo, several things can happen, few of them good.

1. Internal stresses of a machined or molded plastic part can be "relieved" during cryo by internal differential contraction, base contraction around metals, or simple failure at a stress concentration. The vendors do not have the ability to see this at the microscopic level, the casual user certainly cannot. Any plastic part which by design, is supposed to dielectrically isolate two parts, like hot to ground, hot to neutral, and has been structurally compromised by cryogenic temperatures, is a bad thing.

Any feature in a piece of plastic which has been molded in or machined in, incurs the possibility that there are stresses within that will not enjoy cryo.

2. Plastics shrink in the 100+ PPM/degree C range, whereas copper is 16, steel is 12, aluminum is 25. Any metal part inside a slot or opening of a plastic part designed to constrain it physically, will shrink far less than the plastic surrounding it. The metal will not give in this case, but the plastic will. At the temperatures where the forces will be the highest, the plastics are brittle and non flexible.

3. Wire insulation becomes brittle cold. The purpose of the bending radii limitation in the NEC is to prevent insulation degradation over time...if you have an overly tight bend in a wire, the insulation on the outside of the bend is in high tension, the inner is in high compression and typically buckles. Any insulated wire which is exposed to cryo has to, by design, have a defined bending radii considerably larger than code for room temp, as the stressed insulation will crack.

The most dangerous aspect of cryoing parts which have NOT been designed to maintain integrity through the process is that of the failures which are not spotted.

I maintain that there are very vary few (if any) audio vendors out there who have the expertise to know what to look for and where to look for it... to guarantee that what was done to the part did not compromise it's safety.

Polyimide (kapton) is the best plastic for cryo survival as it retains flexibility even in liquid helium. However, it is NOT self extinguishing should an arc develop. It was for that reason that it is banned in all military flight hardware (and should never be used in the home for any wiring). Tefzel is not as good, but is more abrasion resistant and retains some flexibility past liquid nitrogen temperatures.

But honestly, cryogenic treatment does not alter the room temperature current carrying properties of a normal metal, but can alter the physical properties a tad.

Yeah that reminds me of chicken little and the sky is falling.

Do you think they treat the whole outlet or just the metal? Have you even checked? Duh...why let facts get in the way of a good story.

Read the paragraph regarding their cryogenic process..."all metal parts....."

http://www.furutech.com/technology/

 

[MylesBAstor]

It doesn't really do much good to cryo the outlets if the Romex in the walls is left undone. Gotta freeze the whole house.

Tim

Sez someone who's never tried a high quality outlet like the Shunyata or Furutech.

Please explain how you can have a meaningful opinion.

 

[CGabriel]

RE: Cryogenically Treated Wire and Connectors

What Speedskater posted about cryo treatment is partially true. First let me say that we have been treating insulated wires and connectors for about 13 years. Furthermore, we design all of our own wire for our products and we have the HI-POT testers and insulation testers to test the integrity of the insulation, wire, metal contacts and connector shells.

Cryo treatment should only be done by a lab that has a computer controlled cryogenic plant. The operation of the plant needs to be supervised by a knowledgeable staff to prevent serious damage to the parts being treated. Parts should never be subjected to total immersion in liquid nitrogen.

A computer controlled cryo plant controls the release of nitrogen gas into a sealed chamber by monitoring the controlled decent of temperature within the chamber. The temperature is lowered by a degree or two and then allowed to stabilize before releasing more gas into the chamber. This process continues until a chamber temperature of about -320 degrees fahrenheit is reached. Then the temperature is maintained for a soak period of time. Then the temperature in the chamber is raised slowly and in small increments until room temperature is achieved. A total cycle takes about 72 hours to complete.

This controlled decent and ascent is necessary to prevent thermal shock to the materials under treatment. It is also important in how the parts are placed in the chamber and other technical aspects to prevent damage.

We have treated hundreds of thousands of feet of wire and have never found a degredation of the insulation and we DO have the equipment and technical expertise to test for it. The caveat is that all of this wire was treated using the proper equipment and proceedures. There are some plastics that DO get damaged even with proper treatment. An example would be some polycarbonates as used for connector headshells. This is why we only treat the metal parts of connectors before they are assembled with their plastic shells into completed connectors.

I also disagree with the EE that was the source of the information about polyamide (Kapton). Our information from aerospace industry sources is that it is especially sensitive to dielectric strength degradation due to extreme low temperatures as with cryo treatment.

So Speedskater's post is a good warning. Don't give expensive cables or other parts to people for cryo treatment that may not have the proper equipment or knowledge to do it right. Most cryo treatment facilities treat engine and tool parts that are exclusively metal. They do not have the expertise to treat insulated cables and other compound material parts. Even with our expertise and experience we would NOT treat a complete power cable or signal cable. Treating power outlets is not a problem. The plastics are very tough stable and withstand cryo treatment quite well. I have never seen one damaged due to cryo.

Cryo Tubes:
We own our cryo plant and i have used it to cryo treat many things. Guitar strings and flutes have been done to great effect. I have treated many amplifier tubes and have found as some have reported that it either makes them go microphonic quicky or greatly shortens their life span. Just because some guy did it and got away with doesn't mean you will luck out. You want try treating cheap tubes - go for it. But be warned don't try it with expensive tubes.

 

[Phelonious Ponk]

Sez someone who's never tried a high quality outlet like the Shunyata or Furutech.

Please explain how you can have a meaningful opinion.

Not a meaningful opinion. A joke.

Tim

 

[rockitman]

It doesn't really do much good to cryo the outlets if the Romex in the walls is left undone. Gotta freeze the whole house.

Tim

Yes, I foresee a new business op....Cryogenic Tenting of homes the same way they did it for pesticides ala Breaking bad. Just make sure to drain the water pipes...

 

[CGabriel]

Yes, I foresee a new business op....Cryogenic Tenting of homes the same way they did it for pesticides ala Breaking bad. Just make sure to drain the water pipes...

Well funny you should say that. There are companies that use liquid nitrogen injected into the walls to kill termites without the use of pesticides. And there were reports that it can damage the romex wiring.

 

[jap]

I If you twist my arm and say that I can only choose between gold and rhodium plating I would choose.

So, If I can ask without violating the PM Shunyata warning I received from our forum host, which would you choose?

 

[CGabriel]

So, If I can ask without violating the PM Shunyata warning I received from our forum host, which would you choose?

Sorry Jap, the last sentence got clipped accidentally.

If there where only a choice between gold and rhodium plating, I prefer gold. But both are colorations compared to pure brass base metal. You may choose something else depending upon system balance.

 

[LL21]

Sorry Jap, the last sentence got clipped accidentally.

If there where only a choice between gold and rhodium plating, I prefer gold. But both are colorations compared to pure brass base metal. You may choose something else depending upon system balance.

Interesting...are there a lot of outlets and plugs that use pure brass base metal?

 

[CGabriel]

Interesting...are there a lot of outlets and plugs that use pure brass base metal?

Most commercial grade or better outlets claim brass or bronze contacts. Those terms are used interchangeably. Brass comes in many different alloy compositions of copper with zinc, tin, lead and other minor metals. Hubbell outlets use a zinc based alloy which what I prefer. Leviton uses more tin in the alloy which I don't prefer.

All outlets LOOK similar from the outside but there are substantial differences once you take them apart and examine the interior. You want internal contacts that are heavy gauge and use a triple wipe system. This means that it makes contact with the blade of the AC plug on three different surfaces. Next you would like the outlet to have a relatively large air gap between the contacts and the body for better cooling. The contacts within an outlet can get quite hot when conducting large amounts of current. This heat generates thermal noise which can be audible through the audio system.

http://www.shunyata.com/images/products/pwr_dist/difference_contacts.jpg

 

[MylesBAstor]

Most commercial grade or better outlets claim brass or bronze contacts. Those terms are used interchangeably. Brass comes in many different alloy compositions of copper with zinc, tin, lead and other minor metals. Hubbell outlets use a zinc based alloy which what I prefer. Leviton uses more tin in the alloy which I don't prefer.

All outlets LOOK similar from the outside but there are substantial differences once you take them apart and examine the interior. You want internal contacts that are heavy gauge and use a triple wipe system. This means that it makes contact with the blade of the AC plug on three different surfaces. Next you would like the outlet to have a relatively large air gap between the contacts and the body for better cooling. The contacts within an outlet can get quite hot when conducting large amounts of current. This heat generates thermal noise which can be audible through the audio system.

http://www.shunyata.com/images/products/pwr_dist/difference_contacts.jpg

Thanks for showing there's more to the lowly outlet than meets the eye!

The amount of noise reduction with top quality AC receptacles is amazing. Then again, people use 50 cent receptacles that are arced, pitted and corroded and literally fall apart when removed from the wall. Now that's dangerous! That's why the above comments warning about the use of high-end AC receptacles is beyond comical.

 

[LL21]

Most commercial grade or better outlets claim brass or bronze contacts. Those terms are used interchangeably. Brass comes in many different alloy compositions of copper with zinc, tin, lead and other minor metals. Hubbell outlets use a zinc based alloy which what I prefer. Leviton uses more tin in the alloy which I don't prefer.

All outlets LOOK similar from the outside but there are substantial differences once you take them apart and examine the interior. You want internal contacts that are heavy gauge and use a triple wipe system. This means that it makes contact with the blade of the AC plug on three different surfaces. Next you would like the outlet to have a relatively large air gap between the contacts and the body for better cooling. The contacts within an outlet can get quite hot when conducting large amounts of current. This heat generates thermal noise which can be audible through the audio system.

http://www.shunyata.com/images/products/pwr_dist/difference_contacts.jpg

Thank you...very interesting. Presumably you would recommend that plugs themselves be made of a similar material? Brass alloy?

 

[spiritofmusic]

Great stuff gentleman, but my transformer company are going for non-cryo, unplated. And I'll go w/them.

 

[MylesBAstor]

Great stuff gentleman, but my transformer company are going for non-cryo, unplated. And I'll go w/them.

What do you think are in your Tri-Point conditioner? They ain't 50 cent receptacles. One way or the other.

Personally reason that I chose the Furutech GTX-D was that my PLC used them.