Follow up on copper foil speaker cables

man, that was confusing

I didn't realize there were two threads..

Coolin said:



Does anyone know of any software to calculate the impedance of varying conductor geometry?

Yep..
It is an excel ss..What do you wish as the independent variable?

DC, width, insulation thickness, inductance, or capacitance?

Cheers, John
 

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fdegrove said:
Hi,



Do you mean various cable geometries or really varying geometrie?

Maybe this will help:

AUDIOHOLICS

Cheers,;)


Well both actually. But i geuss getting close to 8 ohms is only possible with foil .
This behaves as a transmission line though right?And per length of a meter or something. THis is a rating for in the Mhz though not for DC resistance. This doesnt ensure a good match to the DC resistance of an 8 ohm speaker.
Also the speaker will have much more inductance than the cable.

Or am i wrong?

jneutron and fthegroove thanks for the info.

Coolin
 
Coolin said:



Well both actually. But i geuss getting close to 8 ohms is only possible with foil .

No. It is also possible with coaxial construction and multiple wire pairs and flat ribbon conductors wired correctly.

Coolin said:

This behaves as a transmission line though right?And per length of a meter or something. THis is a rating for in the Mhz though not for DC resistance. This doesnt ensure a good match to the DC resistance of an 8 ohm speaker.
Also the speaker will have much more inductance than the cable.

Coolin

All wires will act as transmission lines...question is if it is necessary to match impedance of the line to the load at audio frequencies.

Yes, the speaker has much more inductance than the wires. But, it is not just the inductance...transient behaviour can be changed by wire inductance.

By matching the line impedance to the load, you also have the benefit of minimized energy storage within the wires...as both the capacitive and inductive storage of the wire will be lag mechanisms. again, modifying the transient behaviour.

Human lateralization falls down into the 1.5 to 5 uSec regime, and this is easily changed by a coupla microhenries at 8 ohms.

Here's a plot of wire energy storage vs cable impedance with an 8 ohm load....oh, I forgot..the energy stored is a result of 100 wrms into that 8 ohm load..and although in the microjoule range, that is significant w/r to a 5 to 10 Khz signal..

Cheers, till tomorrow....John (the magnet "clown" I was referring to)
 

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Re: ribbon....

AudioGeek said:


can you elaborate on hoe the ribbon conductors should be wired correctly for 8 ohm impedance matching?

Hmmm..that article is not really that clear for what you need.

equations:

LC=1034 * DC...dielectric coeff...teflon=2.7, air=1

Z=sqr(L/C)

if you use L=13.5 nH per foot, C is 206.7 pf per foot.

sqr(13.5/.2067)=8.08 ohms impedance.

So, take a wire pair...use the terman equation...

L=.01016*length*[{2.303*log(D/r)}-{D/length}+{mu*.25}]

length in inches
D is center to center spacing of wires
r is wire radius
mu is 1

with that calculated inductance, divide it by the needed inductance..

Ex: #18 awg zip, .080 spacing, r=.020.... 200 nH per foot..

200/13.5=14.8

use 15 pairs to get the inductance you require...the capacitance will be difficult to calc due to proximity effects..but you get the idea.

For a ribbon, alternate + and -, and give it a whirl..

One of these days, I'll try measuring one, to see how the addition of more pairs changes L,C, and Z...

but not now..

Cheers, John
 
I also tried the Alphacore/Cardas recipe Peter shared.

The only commercial cables i had for comparison were Transparent Musicwave PLus and Cabletalk 3.1 biwire. The CAbletalk was quite unlistenable while Transparent sounded amusingly non-transparent.

The copper foil sounds very fast, very resolved, with good dynamics and low perceived distortion, even in loud and complex passages. There might be a minor issue with tonal balance which tends to be on the thin side and relative lack of bass weight but for the cost/effort one needs to be insane to demand more.

Interestingly, i also replaced the biwire jumpers on my speakers with copper foil and the improvement was disproportional to the length.

Now i desperately need more Alphacore to biwire the speakers :)
 
HI Peter
I desided to I give a try to these cable .
I orderd a Goertz .82mH inductor from Partconexion ,some times next week will arive with the BG capacitors together for the gainclone.
I'm looking for that plastic tape what you use for your cable . I check a couple stores like Canadien Tire ,Home Depot ect , unfortunatly I did not found .
Would you please let me know (if is not secret) from were I can purchase that tape .
One more think ,I think I destroed somehow one chip at my gainclone , I dont know if you can help just to sell a pair matched chip so I can replace it .
I want to replace both so they will be the same ..
Please let me know .
Regards
 
I know I'm digging up a old topic here, but I just came across a couple of silver Alpha Core inductors.

I'd like to make a couple of short runs with it for a speaker cabinet re-wire. I'm using their AG2 cable from my amp to the cabs, so why not continue all the way to my drivers.

How's the tape holding up? Will any old tape work?

Thanks!

Mike
 
Indeed bringing up an old post......

I made some ribbonspeaker wire in 2004 and they are still in pretty much the same condition as when I made them. I think there are more small air bubbles in the tape now, but the copper still looks the same.

I used copper inductors from Parts Express (14awg/0.66mh).

I'll see if I can get some pics of them. I used name brand packaging tape from Home Depot. Can't remember the exact name, but it was the more expensive stuff. Anyways it had the thickest plastic film and I figured the glue would be better quality then the cheaper stuff.
 
Hybrid fourdoor said:
Heres some pics. These are current...after 3 years.


Very nice hybrid, but I have a few questions. ou said it was from partsexpress, but I won't order from them as Im in the UK. So:

1: What is the width of each of the copper strips in your cables?
2: Have you trimmed down the ends for the spades?

Finally, how do they sound ?

Im thinking of going for silver foil instead of copper with some cotton insulation. But it all depends on how my new amp sounds with my speakers this weekend when it is delivered.
 
You may have a hard time finding silver foil, Alpha Core hasn't made any in a few years. I just scored two silver inductors off of Audiogon.

My cables came out pretty ugly because I used mylar instead of tape. If I were to do it over again, I would use tape. Luckily, this was for a cabinet re-wire.

As for the sound, MUCH more highs and more detail all around. No loss in bass either.

Needless to say, I'm VERY happy. The only downside, poor recordings sound even poorer.
 
Hi,

Me again, with a message with commermercial content, but on topic :) Jantzen Audio offers a 16 Awg foil cable you might be interested in:

Jantzen%20folie%20kabel.jpg


I sell these for euro 1.93 the monometer, making a connection to a banana or another connector takes some cm experimenting before you get it right.

Kind regards
Roland
 
roland bios said:
Hi,

Me again, with a message with commermercial content, but on topic :) Jantzen Audio offers a 16 Awg foil cable you might be interested in:


I sell these for euro 1.93 the monometer, making a connection to a banana or another connector takes some cm experimenting before you get it right.

Kind regards
Roland

OK more questions from me :D

1. Are you from Jantzen Audio, or are you a dealer?
2. By monometer, what do you mean. As in 1.93 euro for a metre of copper foil [without insulation]?
3. I have looked at the UK prices and they are over 600 pounds for a 660g inductor in silver which waaaaay outta my league. But there are soo many other different choices with various mH values which i don't even know what they are, let alone what would be suitable for me.

Im still interested in making x4 2m lengths to be used as speaker cable.:eek: