Arny Krueger wrote:
"Eeyore" wrote in
Arny Krueger wrote:
"Eeyore" wrote
Arny Krueger wrote:
"Harry Lavo" wrote
Years ago, on RAHE, I described a situation where I bought (used)
some
top-of-the-line Monster speaker cable to replace my basic Monster
speaker cable, and how dissappointed I was that it actually sounded
less good than what I was using...so I took it back.
In fact it probably sounded no different. But Harry always has to hear
some difference.
That perhaps or the extra low resistance altered the frequency response
subtly in a way he disapproved of.
The "top-of-the-line" Monster cables I've checked out have about the same
resistance as the basic Monster cable. It's something like 12 gauge
either way.
The physical differences I've seen related to how the wire was
insulated - single bundle of bare strands versus multiple
separately-insulated
strands, etc.
For years Monster sold speaker cables with separately-insulated strands
as
addressing skin effect. Lab tests that should have shown the tiny
decreased
impedance at high frequencies due to addressing skin effect, didn't.
It turns out that separately-insulated strands don't address skin effect.
You need something like a hollow conductor with a far larger outside
diameter to do that. Later on Monster did come out with a cable that
addressed skin effect, by properly changing the conductor geometry from a
bundle of wires to what amounted to being a hollow tube with far larger
outside diameter.
Of course the larger diameter hollow decreased mutual inductance between
the conductors, which in turn increased series inductance. So they just
exchanged the tiny losses due to skin effect for tiny losses due to
series inductance.
Check out the various styles of Litz construction.
Theoretically, cables made up of fine wires or small individually insulated
wires does not address skin effect. Lab measurements bear that out.
Therefore Litz wire doesn't do a lot for skin effect.
Well..... it has to or high frequency smps transformers would be hoplessly
inefficient.
Having said that there are many forms of construction. Aside from just skin
effect there some kind of magnetic coupling involved too for multiple conductors
but I'm no expert regarding that.
These guys have loads of info on it though. I was evaluating some of their Litz
wire.
http://www.newenglandwire.com/
Graham