What Is The Best Geometry For Power Cables?

[DaveC]

What is the best geometry for PCs? Are there any guidelines you guys have noticed, like configuring the geometry for low inductance? It seems I mostly see twisted pairs and sometimes star quads, which are low inductance, esp. the star quad.

I have made a few PCs with twisted pairs of 12g mil spec, now I have some 14g vintage WE cloth covered wire coming that I'd like to make a few PCs with. I'm thinking a litz braid maybe.... if you use a litz braid with 3 legs, would you include the safety ground in the litz braid or use 2 runs of neutral wire and keep the safety ground outside the litz braid?

Any suggestions are appreciated... 

[richidoo]

I can't say much about conductor geometry, although I understand how it works and believe that it can have a significant effect. I am more swayed by the materials chosen for the conductor and dielectric. Hearing wires made with JPS alumiloy conductor have really impressed me, so I put more weight on that. But JPS may also be using winding geometry that adds to the effect.

[WireNut]

I'm very happy after building these.

http://www.audiotweaks.com/diy/bobcrump_pc/page01.htm

[BobM]

The Asylum cord was my go to cord for quite a long time, besting a lot of others I tried. And it can't be beat for the price.

However I chaned my mind after hearing them vs both the Kaplan cords and the Triode Wire Labs cords. Yes, it is more money for those, but they both are much better.

[DaveC]

I'm sure the Asylum cord is great, but I don't want to buy Belden wire, I am constructing my own cable out of 14g NOS WE wire. I believe better performance will come from geometries other than the standard twisted 3-wire configuration of most manufactured powercords.

It seems TWL is popular here, their website says it is litz construction...

Another PC question, does the safety ground leg contribute to the sonics?

[Werd]

Hello

I don't think this question can be answered. There is too much criteria in pc placement to answer it. The question is too general.

The question doesn't ask if noise reduction is the motive or is it power response? It doesn't ask where the pc is going and what is allowable in sound staging. Do we want a stiff presentation from the source or do we want to color it? I really don't know the answer to my own questions as far as geometry,but that is where I would like a question like this to go as far answers.

[DaveC]

I am going for as neutral as possible, a touch on the warm side is ok. My amp is a low power (5-6 wpc) SET amp, tube preamp, source is a USB DAC. I also use a SurgeX surge protector and line conditioner that needs a new PC, it has a captive cord with a nickle plated male plug. I might just replace the plug though, IDK...

[DaveC]

I'm thinking of doing a 4 wire litz braid with the hot and neutrals paired with their own ground wires.... should balance inductance and capacitance while providing good noise rejection.

[richidoo]

What is litz? 

[DaveC]

This is a 4 wire flat litz braid...

http://www.chimeralabs.com/diy_braid.html

I actually used a helical braid instead of a flat braid... if you can imagine 2 intertwined criss-crossing pairs of wire at a 90 deg angle to one another along the long axis, that's what I did... OK, I will take pics when I get it done. 

I think... or maybe better said is I hypothesize that the geometry of a PC is very important and on the level of materials and connector quality. So, I would guess the PC can act as a filter, depending on it's geometry.

[DaveC]

Here's a couple pics of the finished cord. I tried it briefly on my SET amp and it was a little clearer but not as full sounding and a little closed-in on the soundstage... but that's with ZERO break in so I think it will open up and improve a lot.

I have material to make one more... might try a different geo and see what happens.

[DaveC]

I just put my PC on my DAC, which was using a stock PC w/ a nickle plated male plug.

This made a pretty big difference. I did not try one of my 12g twisted pair mil spec cords on the DAC for comparison yet, I will give the new PC a chance to break in for a couple weeks.

Also, here's a helical litz braid, as done by Shunyata... I have a Jupiter IC using 8 strands of 26g 6N copper and it is a very, very good IC. Here's links to both:

http://www.shunyata.com/Content/technical-HelixGeometry.html

http://jupitercondenser.com/Cable/cotton-insulated-cable.html

[rollo]

Dave the concept of a good PC is deliver more current with less noise. LCR is important in determiming the character of the sound. Windings of such can affect the outcome. As well as grounding schemes. Some designers like the ground wire twisted with the hot and neutral, others run the ground outside the wind. Then there is the Ga. of the ground wire. Should it be of a smaller or larger Ga. ? Ah the 66 million dollar question. The wire itself wether concentric wind, stranded, ribbon or solid core. Then there are designs with multiple conductors of different types. Annealing of the wire appears to great affect on sonics as well.
   so it appears not an easy task to get it right. Experimentation and measurement is key to any design. Trial and error.
  Now with all that power cord "A" will not sound the same with different components. The power supply of such is a major factor as to what the PC will do.
   Just remember one size does not fit all. As of this writing we are using a combo of cords to achieve sonic nirvana. All TWL Labs on components and Omega Mikro Active on the UberBusses.. Waiting for two more TWL 7+ cords to compare directly to the Omegas. The Omegas in the components do not achieve the sonics of the TWL cords. Just too bright. In the Uberbuss compared to theTWL 8Ga cryoed we preferred the Omega.  Why does that combo work out better for us ? I just do not know.
   As an aside the addition of the second Uberbuss to the system, one for amps and one for all else was a win win. Better than ANY powercord combo tried.
   Last but certainly not least is maintaining bright and shiny contacts.  A clean connection is a good connection. Progold for all.

charles

[DaveC]

Thanks rollo.

One thing that has me a little baffled is the difference between neutral and ground as far as how they would interact with the power wire and produce different LCRs. Neutral and Ground are connected together at the main panel and both go to the same ground point, either a stake or a copper water line. But I suppose the neutral is really used as the "return" and ground just as a safety... so it would seem to me that neutral would be the wire to reference to the power wire and safety ground could be left outside the main geometry. This is how I made my 12g twisted pair PCS, the ground counter-rotates around the twisted pair of hot+neutral.

I made a star quad using exactly the same wire and connectors as my 4 wire litz braid, should be interesting to compare them... I'm also going to try running the PCs as 2 wires for hot, 2 for neutral, and an exterior ground wire instead of their current configuration, which is red wires are hot and neutral, black wires are both grounds.

[BobM]

Here's a link to a discussion on this very topic over at AC

http://www.audiocircle.com/index.php?topic=10004.0;imode