Thoughts on these...and amorphous wire

Magnet wire resistors, enough to make any engineer scream.
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Ed Sawyer

Thoughts on these...and amorphous wire

Post by Ed Sawyer »

Forgive my ignorance. These sound like an interesting idea, say for Cathode resistors. How would they differ from NIWW (non-inductive wirewound) resistors like those power resistors wound on ceramic cores? I presume those are nicrhome wire or something with a lot less conductivity than copper? How big would say a 12w/1k5 resistor be, doing it the Dave way with copper/teflon? If going off the deep end anyway, how about silver wire ones? ;-)

On the topic of wire, Dave - being an amorphous kinda guy, have you looked into amorphous wire at all? Apparently it's fairly rare and expensive. The guy from Stealth cables apparently lucked into some somehow (in ex-Soviet Russia perhaps), and is making huge $ on selling it in interconnect cable form (Stealth Indra cables, like $5k/1m pair)... seems like he is cashing in on his luck in a big way, probably since he'll never find that wire again. (talk about a good score). Reading the Stealth site it doesn't offer much insight into where to source it or anything really - obviously he fell into some dumb luck and is capitalizing on it, ... but anyway - just wondered if it's something anyone has played around with at all.

-Ed
dave slagle
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Post by dave slagle »

ed wrote: How would they differ from NIWW (non-inductive wirewound) resistors like those power resistors wound on ceramic cores?
well, they are decidedly inductive, they have large capacitance, and they change value with temperature.
I presume those are nicrhome wire or something with a lot less conductivity than copper?
yes essentially all resistors are crappy conductors, this always struck me as ironic that people will go for exotic copper and silver for a foot or two of interconnect only to feed the signal through something desinged not to conduct. Somehow common sense tells me there is something really wrong with that. The copper resistor, just uses a long lenght of very good conductor rather than a shorter length of a crappy conductor. the problem comes with the added baggage above of the L C and temp issues.
How big would say a 12w/1k5 resistor be, doing it the Dave way with copper/teflon?
the basic size at the moment is on a 3/4 inch by 6 inch teflon tube... let me know how much current you need to run and we can work through it and discuss the supposed pitfalls and how ot best deal with them. I went with a tube and an open ended design to allow for the heat to dissipate. not sure if teflon is needed, but it can't hurt. :-) wattage really isn't the issue, acceptable temperature tolerances are. as to what those are... you gotta try it and report back. math and excel will help us a lot here. If i send you a resistor and ask you to measure it, based on the accuracy of your meter (and mine) i can tell you the temperature of your room.
If going off the deep end anyway, how about silver wire ones?
i gotta give all kinds of props to the audioconsulting guys... sometimes i feel like i am ripping them off and should be paying them some sort of kickback.... those guys are really ahead of the curve and get way too much ridicule from people on the various boards. For silver they are the people to contact.
On the topic of wire, Dave - being an amorphous kinda guy, have you looked into amorphous wire at all?
well chris vryondies was in town a bit ago and we were having a chat. (i'll point him to this post) and it seems he bought some small cobalt amorphous toroids to play with. The odd thing was he said they had endcaps on them and if you removed them, you had a long roll of amorphous tape that you could just unroll !!! then he mentioned the very same idea of amorphous interconnects and referenced the commercial ones out there. the amorphous tape is .001 thick and allen wrights foil interconnects comes to mind... the other interesting thing that comes to mind with the amorphous tape is how about an cobalt amorphous and teflon cap :-) you should be able to charge a gazillion dollars for that grouping of catch-phrases.

on a more serious note and to bring this back to the realm of reason, i have wound chokes with alloy 60 magnet wire (nickel copper blend) and the things sounded awful... so beware of catch phrases.
shinebox

amorphous wire...

Post by shinebox »

Allo fellas,
What I'd love to know is if the Stealth stuff is magnetic... cos I know a source of amorphous wire... Brit company, "Goodfellow". They are super super expensive, particularly for small quantities - they supply all sorts of metals, compounds etc to research labs.

But still not "audiophile pricing" in some cases...

If ya go to
http://www.goodfellow.com/csp/active/gfHome.csp
and search for "amorphous wire" you'll see it.

I don't buy a lot of industry BS about stuff being sourced from beyond the stars or whatever, but the issue with the above stuff is it's magnetic - after all, it's the same sort of composition as the C-cored stuff we know and love. If the Stealth is non-magnetic, that may be more tricky.

You might be able to turn the other stuff non-magnetic by very carefully controlled heating, but you'd obviously need to ensure you didn't get it to recrystallise.

The cheap alternative, as Dave alluded to, is to get a little cobalt alloy toroid, pop the end caps, and unroll the stuff. It's quite flakey though; mechanically would be a nightmare...

I got 1 spare core I can send out if anyone's game.

I can't imagine a worse capacitor than one wound with magnetic foil.... but I think Dave's onto something as goes its BS potential...

Cheers,
shinebox aka CV
Ed Sawyer

Further thoughts

Post by Ed Sawyer »

Good info to share! the Goodfellows stuff is pricey but not THAT bad, esp. compared to the usual so-called high-end cable rapists like Transparent or Monster. ;-)

I believe the termination/mechanical issues with the Stealth cables were supposedly the biggest challenge. Reportedly, sergei or whomever he is had to invent some new sort of RCA connector to terminate the amorphous wire since apparently it can't be soldered. Brittleness and such was also an issue somehow. It is a very very thin conductor, reportedly, according to what is on the site.

The ribbon from unwinding a toroid would be a cool way to get some stuff to play with for a reasonable price possibly. Agreed the mechanical issues will probably be the biggest challenge. Then of course the magnetic issue. :-/

I am not sure if the Stealth Indra stuff is magnetic or not. The sales/distributor guy is in NH, I met him @ CES so chances are I could catch up with him and pick his brain about it a bit if need be.

re: Caps from cobalt/teflon- LOL hell yeah, go for it! How about mesh amorphous with teflon, silver leadout wires and encase it all in a copper tube with beeswax endseals. Those should be able to sell for at least $1000/.1uf I'd think.

re: the Audioconsulting guys - good to know they know their stuff when it comes to silver and such. Will have to look closer into that. But oh their prices... damn. Just insane! I am getting a nosebleed just thinking about it.

thanks for the fun discussions
-Ed
April155
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Post by April155 »

Nice information. Good post ! :lol: :lol:
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