Dave Plowman averred:

: In article ,
: Duncan Armstrong wrote:
: Top notch high end stereo i/c, got rave reviews in all the mags, uses
: Ecosse's legendary Monocrystal copper (not that I know what that means
: ).
:
: Neither do they. Their ad man made it up.

Maybe. Maybe not.

Metal dealers seem to think "monocrystal copper" means *something* ...
http://www.industrycommunity.com/man...sages/160.html

Ecosse speak of "Monocrystal™" in their "patented" audio cables
http://www.ecossecables.co.uk/Frames...rame.html#mono
-
"Monocrystal™
about our patented unique conductor technology
MONOCRYSTAL™ pure copper and silver is Ecosse's pioneering commitment to
conductor material development ensuring, uniquely, a complete lack of
'grain-boundaries' in the signal transmission direction- impurities which
would normally impede the delicate audio or video signals and result in
attenuation and distortion.
Here, a unique casting process (extrusion and annealing) is employed to
produce a 'mono' or single crystal ultra-pure wire with significant
advantages over other cables currently available. These other cables use
ordinary copper or silver, which, no matter how few grains the manufacturer
claims, have a grain barrier of oxygen and hydrogen.
Monocrystal™ patented copper and silver cables are technically unsurpassed
for their quality and their ability to transmit audio and video of the
highest quality with minimal distortion and attenuation from grain boundaries
- BECAUSE THERE ARE NO BOUNDARIES!
A thirty-day money back guarantee and an unconditional ten-year guarantee
support the Company's absolute confidence in Monocrystal™ quality.
N.B. Audiophiles should note that it is the purity of 'grain structure' (not
to be confused with purity of copper or silver employed - often expressed as
99.99% or better - and merely signifying the purity of the copper ingot
before smelting) which defines the major characteristics in the conductors
ability to transmit audiophile quality sound and video. For the record,
Monocrystal™ is 7N's pure!
_

[Elsewhere they blither on the usual adspeak nonsense about skin effect ...]

Tara Labs claim a "proprietary annealing process" (did they just order their
wire in, from, uh, the proprietor of the annealing process?) for their
SA-OF8N® Copper, and up Ecosse in the "9s" numbers game ...

They also speak of "Monocrystal™". Whose trademark is it??[*]

http://www.taralabs.com/tech_terminology.asp#50
"Super Annealed - Oxygen Free Eight Nines Copper (SA-OF8N®) is the new
standard in high-performance copper purity. Variances in copper purity will
result in audible differences. It is generally accepted that a purer, more
conductive material can be more accurate and revealing that a material that
is less conductive. TARA Labs' proprietary annealing process, known as Super
Annealing (SA), along with Oxygen-Free Eight Nines Copper (99.999999% pure)
creates a unique, long, unbroken crystal structure called a "Monocrystal™" "
_

[They say they eliminate the "skin effect" with wahaha! rectangular cable!]
http://www.taralabs.com/tech_terminology.asp#43
-
"Because of its rectangular cross section, an RSC conductor essentially has
no center like a round conductor. Therefore it does not suffer the same
high-frequency losses. It is the only conductor that is able to combine high
current-carrying capability with extreme frequency linearity across the
musical spectrum."
-
Wow, "essentially" no centre! What a spin! But I digress ...
[*]This article asserts that Tara Labs has the trademark for MonoCrystal
http://home.worldonline.dk/isl24678/...forklaring.htm
"Super Annealing, SA-OF8N and Monocrystal are trademarks and/or registered
trademarks of TARA Labs, Inc." Yet Ecosse write about "Monocrystal™ patented
copper and silver cables" ... wonder what they patented? Are they
acknowledging the trademark, or passing it off as their own? Odd...


A process for producing "continuous grain" copper and some background:
http://www.musicpoint.nl/Furutech/furutech_occ.htm

This is an interesting page (I'd seen before) with photos of microstructure.
-
extract
"In 1986 the Ohno Continuous Casting (OCC) process was introduced. The world
patent "UP-OCC" (Ultra Pure Copper by Ohno Continuous Casting Process) was
developed by professor Ohno of Chiba Institute of Technology in Japan. This
technology has been applied to the manufacturing of single crystallized
copper with the process of heated mold continuous casting. The resulting
product are small rods of OCC pure copper, from which the wire can be drawn
and which can have Copper grains of over 700 ft length."
-

Finally,
http://www.copper.org/resources/prop...e/coppers.html
has some micro photos of some lower grades of copper and other info.
It would seem clear that the material between grains is cuprous oxide.

Eliminating that by drawing one crystal as above might have some benefit.
Whether this benefit is audible in 1m of cable connecting equipment with
longer path lengths of lesser copper and many joints internally - debatable.

Fig 3 in another page shows that higher purity copper has a slightly higher
conductivity (about 2%?) than the standard 1.0 used for normal grade ...
http://www.copper.org/innovations/19...etallurgy.html

I wonder if that would gain any worthwhile benefit in say a transformer.
OTOH one can already fork out for silver wire transformers ... and presumably
the same process could be applied to silver if it were really desirable;-)

On the macroscopic level copper also exists in nature in crystalline form.
Well, all metals have crystals at a microscopic level - I mean large ones.
A search on "copper crystal" will turn up a few pics of native copper.
http://www.davidkjoyceminerals.com/h...sp?TitleID=233
http://webmineral.com/data/Copper.shtml has a rotatable crystal sketch.

Particularly WRT the Furutech link above, the term monocrystal would seem to
have some meaning. I'm not quite sure if the term as used by Ecosse and Tara
Labs, seemingly synonymous with "grain" there, has the same meaning as
"crystal" in the scientific sense, on the macro or micro level. Perhaps.

In any case, it's demonstrably more than mere "adspeak":=})