diyAudio

diyAudio (http://www.diyaudio.com/forums/)
-   Planars & Exotics (http://www.diyaudio.com/forums/planars-exotics/)
-   -   Coax speaker cables? (http://www.diyaudio.com/forums/planars-exotics/227259-coax-speaker-cables.html)

CharlieM 7th January 2013 10:01 PM

Coax speaker cables?
 
I'm seeking opinions on going with Mogami 3082 coax speaker cables for my hybrid ESL's.

I've read Roger Sanders' cable white paper and I also read this review of the Sanders cables, wherein, it says they use Mogami #3082 coax cable:
http://forum.audiogon.com/cgi-bin/fr...Speaker-Cable-

Mogami's spec sheet for 3082 cable (see below) states its capacitance is 77pf per foot, which may be low relative to its inductance, but is still higher than other [non-woven] cables I've read about.
http://www.mogamicable.com/category/...le/pure_sound/

Unfortunately, I'm a complete dummy concerning all things electronic, including the effects of inductance and capacitance on loading an amp and on the resulting sound of the speaker.

Asking for advice now is a bit like closing the barn door after the horse is out, since I had already ordered some Mogami 3082 cable and connectors to build a pair of 10ft cables. But that was before I found the spec sheet and noted the higher capacitance. And I'm also assuming the review I read is correct regarding the Sanders cables using the Mogami wire. It would ease my mind if I could be sure that accepting the higher capacitance for lower inductance is in fact a good and wise trade.

Any thoughts on that?

bear 7th January 2013 11:21 PM

your link to the other forum does not work.

I do not think coax is a good choice for speaker cables.
Others may feel otherwise.

Not sure what Roger Sanders is saying, but he is driving ESLs, that changes the equation somewhat I expect.

In general I have not liked the way higher capacitance speaker cables sound, but there can always be exceptions and new experiences.

CharlieM 7th January 2013 11:26 PM

Quote:

Originally Posted by bear (Post 3315615)
your link to the other forum does not work.

I do not think coax is a good choice for speaker cables.
Others may feel otherwise.

Not sure what Roger Sanders is saying, but he is driving ESLs, that changes the equation somewhat I expect.

In general I have not liked the way higher capacitance speaker cables sound, but there can always be exceptions and new experiences.

I should have clarified: The Sanders white paper I referenced applies specifically to driving ESL speakers.

Dumbledog 7th January 2013 11:45 PM

I read some stuff online about cables (so I'm regurgitating here) but you want low inductance low capacitance, otherwise some amps can go hay-wire, especially when it comes to capacitance values. 77 pf per foot is higher than regular zip cord, but some speaker wire can be over 100 pf/foot in order to have lower inductance. I couldn't view the links, but coax cable, due to its design, is prone to higher capacitance. I made myself some litz-like cable out of the wire from some cat-5 cable. Litz cable is good when it comes to low capacitance (given + and - aren't twisted or woven together), relatively low inductance, and low resistance.

CharlieM 7th January 2013 11:49 PM

Here's the review that wouldn't open in my first post:
AudiogoN Reviews: Sanders Sound Systems ESL Speaker Cable Speaker cable

Mogami spec sheet:
http://www.mogamicable.com/category/...le/pure_sound/

Dumbledog 8th January 2013 12:16 AM

I still cant get the Mogami link to open.
What it boils down to is this: having multiple conductor cable, with each conductor individually insulated, having the positive and negative conductors highly coupled (by being closer together) leads to more effective cancelation of the magnetic fields that each create, and thus lower inductance. But since they are closer together, the capacitance between the cables is higher. The difference in sound that you get with different cables is usually pathetically small (especially compared to the price of high end cables), though any difference is usually more of an effect the capacitance/inductance of the cable has on the load that the amp is driving. Some amps can be very sensitive to increases in capacitance in the load, some inductance.
That being said, the cable does have an effect on the signal itself, though minor. Skin effect comes into play at high frequencies, and Maxwell effect at low. So you want a big enough single conductor (24-26 gauge) to counteract skin effect, but no thicker because then Maxwell effect comes into play with thick conductors. But one thin conductor has high resistance, so multiple in parallel are used to lower resistance. How those multiple in parallel are arranged is where inductance and capacitance come in.

Coax cable leads to very low inductance, though the arrangement of the conductors (I assume one of them is a shield around the others since I can't view the link) leads to higher capacitance. It's a game of compromise and some experimentation. That being said, the review of the Magomi cable sounds pretty positive.

CharlieM 8th January 2013 12:35 AM

Thanks Dumbledog,
I can no longer pull up the Mogami website at all so it must be down this evening. As I recall, capacitance is 77pf/ft and inductance 0.12H/ft. The cable is advertised as flexible with a stranded rather than solid center conductor. Both conductors are oxygen free copper and both 14 gauge, with PVC insulation filling the space between the center and outer conductors. I gathered from the Sanders website that the outer conductor is not woven and its strands are spiral wrapped opposite to the twist of the center conductor strands, to better cancel inductance.
Thanks again for your reply.

Dumbledog 8th January 2013 01:15 AM

Ahh... So is the Mogami cable you are talking about instrument cable? Intended for stuff like electric guitar cables and such? If that's the case then it would be interesting to see how it works. Those usually contain high quality wire, though the center conductor is still not like litz cable with each strand being insulated. Think of it more like standard zip cord with one of the wire's conductors wrapped around the insulation of the other wire.

CharlieM 8th January 2013 01:20 AM

It's advertised as "speaker cable". Here's a link that should open:
http://www.performanceaudio.com/medi...137/5636_s.pdf

Dumbledog 8th January 2013 01:58 AM

The stats on that stuff look pretty good. 70 pf per foot is relatively low for the inductance. Same basic design as instrument cable, just with more conductors for intended higher power handling. I'm interested to hear your impressions of it.


All times are GMT. The time now is 03:27 AM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright 1999-2014 diyAudio


Content Relevant URLs by vBSEO 3.3.2