The Great Cryo'd Outlet Test

I tried a cryo'd HBL8300 (Porter Port) and a normal 8300 in my system, first with the EMC-1 UP and then on my Aleph P. Couldn't hear a difference. I then simnplified to just using the EMC-1 alone, fed DIRECTLY to Senn HD600 cans through the RCA outs via adaptors (surprisingly nice match, yet a bit loud), and STILL couldn't hear a difference. Thought I'd at least catch some difference in the top octave somewhere, but nope.
All circuits are discrete 83803EST dedicated lines, 35' long, via my PCKs. Again, my mind's open to cryo's possible effects, but I remain believing that it's the possible reduction of dielectric effects of the INSULATORS consequent to cryo-ing their adjacent conductors that yiels a possible improvement. Yet for some insulators (especially Teflon), there are better ways to accomplish this "curing", but my intent isn't to bend the thread here.
El, I too would REALLY simplify the test systems, to the point of allowing at least 48 hours gravitational settling and isothermality before swapping the test objects. Using cans directly from a source might at least reduce other variables in the chain, too. Bigger problem is going to be the implementation of at least single-blind methodology, preferably in the dark, unless you can recruit your wife with a bribe of some sort...and how to categorize your results, and their interpretation. (PS Jewelry usually works with Ellen!) Have fun.

Interesting, El. But then why don't STRINGS sound different after cryo? As well, my Steinway took TWO years for the stretchier Swedish strings to stabilize, requiring tuning every couple of months. Now, after 4 years, it's held a tune for 13 months (to MY ears...uh oh!). Other strings atabilize more quickly, but don't apparently sound as good...or aren't favored for another reason. Wonder if cryoing piano strings could change their elasticity curve somehow. Doubt it, though.

I have a close friend who's a piezo-transducer wiz, making what are arguably the best pickups for acoustical instruments, and OE supplier to the guitar giants, too.
He told me there was a cryo-craze back a few years ago among the guitar string manufacturers...but it proved to be not real to ANYONE after awhile. And there's where you'd REALLY expect to hear a difference. He's also tried cryoing his ultrasensitive pickups somewhat, but has no positive expectation. His engineers and test people obviously have sensitive ears, always listening for not-yet-measurable artifacts that nevertheless sound "better" in transducing an acoustic vibration into an electrical one to his staff and the large group of pro musicians who endorse his products (Fishman Tansducers). Cryo is certainly NOT on the list of manufacturing tricks....
I'm willing to make up a couple of my PoBox9 with one each cryo and non-cryo duplexes, unmarked, to send around for trials. Hard-wired PC will be my PCK9. The problem, of course, is that we're only adding MORE hardware in the chain, and since performance WILL be determined partially by duplex and circuit line upstream, the additive hardware itself may slightly mask any diffs between the test objects (the dupes). In other words the dupes may get duped....

Psych's comic comment has an element of usefulness (!).
It's my belief that isothermality has a good deal to do with assuring stable performance of many sensitive instruments. I'm of course biased toward thinking so after spending a decade calibrating lab measurement products in an isothermal environment. It's certainly the case that many audio components sound best, or at least consistent, at an operating temperature plateau. I notice that Nelson Pass designed the Alephs (my monos) to run at +25 above ambient, up to a cutoff at 175 if I remember. Certainly they sound "better" after an hour or two's warmup...some say days! Is this because a SPECIFIC temperature is reached? Probably not...just a STABLE temperature, as intimated by "25 above ambient". I keep mine in a WAF-friendly position hung under my rafters in the basement under the speakers, probably about 55 down there. Would they sound better in a 75 degree livingroom? My best guess: probably not, as the heat-cycle they operate at is simply +25 above ambient, and stabilizes there....
But I think it's not always that simple. With PCs and duplexes the hope is both to NOT have a consequent voltage drop associated with increased electrical resistance as a function of conductor temperature fluctuations...or even stable reductions, perhaps....
We all know that heavier gauge conductors have lower electrical resistance, all other things equal (inc. metal composition, geometry, insulation, etc.), and assume that greater dynamic expression occurs because the heavy conductors can somehow "pump" more current. I believe the use of heavy gauge conductors can benefit performance not because of actual increased current handling per se, but only as a function of vltage fluctuation due to tiny temperature changes due to changing resistance of the conductors when large current swings occur. These current demands will be governed both by design paramenters of the component, but their FLUCTUATIONS are more a function of power supply design. Hence one reason why some components sound better with big PCs and some don't. Regulation and "damming", I guess....
(To finish the PC analogy, and yes, to get my plug in, Psych, any means used to STABILIZE the temperature of a PC or duplex, switch contacts, etc., can only be a good thing.
I've learned that heat-sinking a modest sized PC can make it "sound" as dynamic as a larger one, yet, due to lowerinductance, also sound more transparent. Hence my Prelude & Fugues....)
But back to the duplexes: it certainly is an attractive idea to believe that a "rearrangement" of the brass metal matrix of the dupes' contacts due to a process like cryogenic cooling yields a change that at ambience might result in less "resistance" of sorts to current flow, and thus less heating of the contacts. This could be measured, but maybe not easily enough...especially with normal audio componentry. The reasonably-heavy contacts used in Hubbell and Pass & Seymour 5000 and 8000 straight gauge dupes will handle kilowatts of constant power without getting VERY hot. But if the spec is +10C, for example (+18F), then a simple contact thermometer may be useful if implemented carefully to compare two dupes when used with constant kilowatt loads. It would be postulated that the cryogenic treatment results in "cooler" running....
Further, and more practically important for our purposes, the hope is that cryogenic treatment somehow reduces the FLUCTUATION of tiny temperature changes around ambient steady operating temperature, which perhaps could be associated with audible differences. Certainly with a low-current front end component, for example, the difference between a 10AWG and 14AWG PC, ALL OTHER THINGS BEING EQUAL, is NOT audible (this is very hard to test because inductance changes with size and geometry). So there's something else that matters here. Could it be that cryoing the conductors results in improved isothermailty even at miniscule levels? Since I have yet to hear a difference with cryo'd contacts or wires, but hear BIG differences depending upon the different DIELECTRIC involvements associated with various insulations...and their geometry, to a lesser extent, I'm temped to simply deduce that possibly a cryogenic treatment can perhaps "cure" the cheap insulations used in some PCs, and especially duplexes. Again, if violin strings and ultrasensitive piez0-electric transducers don't sound different after cryoing I would suspect more that it's the "curing" of the plasticizers in cheap insulations that might be accelerated by ANY thermal treatment process...perhaps including cryoing. Yet most "curing" of "plastic" materials is performed by relieving residual manufacturing stresses by reheating...not cooling. But maybe metals are different, and since I have no background in metallurgy, I haven't a clue. I just "cure" Teflon. If someone would make a duplex out of PVDF or another nice hard fluorocarbon my EST process could cure it for good, and THEN we'd all have a pretty remarkable duplex! Stable Teflon and high-copper content brass contacts. Anyone got $50k for a mold? Cheers.

I remember once back at Brown in the 70s a friend of mine and I tricked a third friend into thinking he'd dropped acid with us. For an entire day he simply tripped alongside. We didn't own up to it until much later; he could NOT be convinced that he just swallowed an inert ink-spot! Cruel times....