I like this guy

[Coytee]

Gets one thumbs up from me so we just need someone else to get him two thumbs up!

[Y]

http://www.audioasylum.com/cgi/t.mpl?f=prophead&m=60100

I have been an audio person for more than 50 years starting at 10 years old when
I first experimented with tube amps. Worked some 40 years in radio broadcast
engineering on many audio systems.
When repairing or designing custom audio gear the process has always been run
freq and distortion test first, then listen.
Occasionally I come across ads
for audiophile components that I have to wonder what sort of test verify the
claims other than it sounds wonderful. I happen to find a classified ad for a cable on another audio site
that I would really question. First it's said to be an active cable, since there
is no power source I can only assume it does not have any active components.
Then they call it a pseudo balanced cable because they have run two wires
through the cable with a resistance connected from each wire to the shield
ground. In a balanced cable each wire is 180 degrees out of phase with each other so that any noise induced
into the cable is then in phase and cancels at the balanced input. I went to
their web site and I didn't see any mention of how they claim their cable works
so I copied the classified ad and pasted below.


"After two years of
development, Axxxx Txxxxxx Axxxx is excited to introduce our active cable
system. This revolutionary technology expands the possibilities of any system.
Unlike common cables, ACS allows the interconnect to act like a balanced (XLR)
cable. Purity, huge dimension, and great detail are the hallmarks of this
design. This auction is a limited time introductory offer so bid now.
Here is how ACS works. The signal lines
are connected to the shield by a pair of specifically manufactured resistors.
What is created is a pseudo balanced interconnect, as the shield is effectively
neutral relative to both conductors. Relative to the equipment ground, the
shield sees half the signal voltage swing. Einstein would ask, what if the wires
do not know that ground is ground? The results are stunning! This creates a true
actively shielded cable just like Synergistic Reasearch or Audioquest. The sound
is holographic with the speakers disappearing and a gigantic soundstage is
created. Only an active cable can do this. We need to talk about the importance
of a good connector. Large chunks of shiny metal are like a roadblocks to your
precious signal. We use world
famous, Swiss Neutrick connectors. These are a
low mass design which may not look impressive but they deliver the sonic goods
in a big way. The conductors are a proprietary, high conductivity, ultra pure
material. Cable is 1m long."


The ad is completely void of any
technical test data that one might expect, most likely because this cable can
not possibly act as a balanced XLR cable. Regardless of how many wires they run
through the cable it's still unbalanced. Since this is basically a high
impedance unbalanced cable there may actually be some audio degradation from the
extra wire capacitance in the cable.
I see other cable ads like this that use
an array of descriptive words but no actual test data. If one were going to
purchase a new amplifier you would want to see some actual test data. Why then
would you not want to see some actual test data for an expensive super cable?
For instance, just exactly what is the SWR (standing wave ratio) on a low SWR
audio cable compared to a normal audio cable.

[Daddy Dee]

thumbs up from me too. I'd love to see the link to which he is referring.

same folks that do magic pebbles, i suppose.

[Daddy Dee]

ok found it

http://www.auralthrillsaudio.com/selfactive.htm

[Gilbert]

ok found it

http://www.auralthrillsaudio.com/selfactive.htm

2-Thumbs Up here,..... I'm still waiting for someone to invent Organic Audio Cables.

Dee, your like a faithfull ole coon hound. No one has to point you in the right direction, and you always come through.

[Don Richard]

Warning! Snake oil for sale.

As far as SWR on audio cables, 1/4 wavelength is the minimum distance necessary for a standing wave to form. The electrical wavelength of a 20kHz wave is about 9 miles. So if the cables are over 2 miles long there may be a problem with standing waves.

[lo123]

Blue Jeans Cable has good technical articles about many types of cables on their website, link to index below.

http://www.bluejeanscable.com/articles/index.htm

[djk]

"So if the cables are over 2 miles long there may be a problem with standing waves."

The speed is dependent on the dielectric constant as well, with Teflon the speed drops to 0.5C, or 1 mile for your example.