Follow up on copper foil speaker cables

[Peter Daniel]

I've seen that thread long time ago: http://www.diyaudio.com/forums/showthread.php?s=&threadid=9620&highlight=cables
and the idea seemed interesting enough so finally I decided to try it. So here's my implementation of the cables.

 

[Peter Daniel]

I used those 0.1 mH Alpha Core, 14ga inductors and one coil contains enough foil to make 4 lengths of 6' ea. It is also pretty thick and easy to work with.

 

[Peter Daniel]

To insualate the foil, I used that plastic tape (with advesive on one side), I buy locally. It is 5" wide and I cut it into 4 strips, 1.25" wide. The foil is exactly 1" wide, so the plastic film tape can conveniently be attached to both sides of copper foil. I use separate cable runs for positive and negative side. Termination is done with Cardas spade lugs and heatshrink tubing applied.

The cost was about $30 for everything and it took about 2 or 3 hours to complete (both of my kids where giving me a hand and we had a lot of fun in a proccess).

As to the sound, I'll be cautious enough by saying that I didn't compare them to any other cables. But when I installed the cables in a system, I don't feel like I want to replace them. The detail is amazing, very good tonal balance and nothing that could be annoying. Highly recommended.

 

[jwb]

Did you laminate the positive and negative runs together, or separately? WIth them laminated together I imagine the cable would be capable of fairly high frequencies.

 

[jleaman]

Looks interesting. i seen some stuff here at the audio store locally and it was very expensive. 2 conductor and it was laminated side bye side. about .5mm thick. and about 56.oo a foot i believe.

me im going to start making some of my own i like the idea of braided wires so im going to buy a few rolls of single stuff and weave my own.

here is the right cable from my cd player that i used for a while i like the colors. : O ) Now i just need to find more of these color's now..

 

[Peter Daniel]

Did you laminate the positive and negative runs together, or separately? WIth them laminated together I imagine the cable would be capable of fairly high frequencies.

I decided to laminate the runs separately. I know that Goertz does them together.

Any advantages/disadvantages to both methods?

 

[jwb]

Controlled impedance would be one. A wide, flat cable is ideal for microwave frequencies and higher. With the two wires laminated together you would have a controlled (and probably extremely low) impedance transmission line. Of course, you would need to investigate the electric properties of this plastic tape.

At audio frequencies, who knows. But when I see a wide, flat cable I think microwave.

 

[Hybrid fourdoor]

I used those 0.1 mH Alpha Core, 14ga inductors and one coil contains enough foil to make 4 lengths of 6' ea. It is also pretty thick and easy to work with.

Haha, way to think outside of the box. I see those are about $7 a pop...not bad! From the looks of it, it looks like they are already insulated as each layer has some plastic, or is it just plastic between each layer of foil...kinda like 2-ply toilet paper (lack of better example)

You said you used a 0.1mh inductor, do the bigger value inductors just have more windings, or do they have physically bigger foil?

 

[Peter Daniel]

They have more windings as gauge stays the same. To tell the truth I didn't expect so much linear feet of copper foil from such small coils.

There is a plastic tape between windings, but it's not attached.

 

[Variac]

Hi Peter,
Are gainclones stable into these cables?
How about a son o Zen?

 

[Peter Daniel]

No problem with GC, I believe SOZ wouldn't mind either

 

[Variac]

I think the potential problems are if the 2 conductors are stacked.
From reading this thread it looks like this might also confer benefits though. Maybe you could place the cables you made on top of each other as a test to see if stability/sound changes.

 

[planet10]

Originally posted by Peter Daniel I used those 0.1 mH Alpha Core, 14ga inductors and one coil contains enough foil to make 4 lengths of 6' ea. It is also pretty thick and easy to work with.

Do you know how thick the foil is? In theory the thinner the better.

dave

 

[Hybrid fourdoor]

SO basically way cheap Nordost?

 

[SY]

Peter, this gives you a good way to compare the effects of varying L and C. Foil over foil will maxximize C, minimize L. It would be interesting to see how your chip amp responds to a high-C load. Do you use an isolating inductor?

edit: I see that Variac has made a similar point.

 

[Peter Daniel]

The foil is 0.05mm or 0.002" thick.


I think it's better to have both runs separately, as the capacitance is less. In case of interferences (which I didn't have any sign of) you can always stack them together.

 

[roddyama]

They have more windings as gauge stays the same. To tell the truth I didn't expect so much linear feet of copper foil from such small coils.

There is a plastic tape between windings, but it's not attached.

Below is a special .05mH @ 14ga next to a 1mH @ 12ga. For Peter, I show a "two-ny" to gauge size with. The two-ny is a little over an inch in diameter and worth about $1.25USD.

 

[JOE DIRT®]

good concept but a little fragile for me to use with dogs and cats and kids running around the house....and worse the better half is deadly with the vacuum she would destroy that in a second

 

[Variac]

In another discussion of this topic I believe someone said that you have a choice of high impedence/low capacitance or vice versa- you can't have both. So not stacking is not a free lunch.

 

[Pjotr]

Hi all,

I was also considering using copper foil coils for speaker cable some time ago. The coils available here are of 0.07mm x 25mm copper strip. I was considering mounting the copper strips sandwiched between 2 cut mylar strips (0.2 mm thickness) with 3M high performance double sided adhesive tape. Mounting the copper strips side by side.

As for now I stick with 50-strand computer flat cable. With this I am more flexible to balance inductance versus capacitance.