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alxlwson

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I've seen many people recommend using solid core wire for their speaker cables. Now, speaking as an industrial maintenance electrician, I say this is absolute madness. Why do I say this? Skinning! The skin effect is very well documented. High frequency signal/power tends to travel on the outside or the skin, of the conductor rather than "saturating" the conductor. So in my world when dealing in VFD(usually up to 240Hz) applications, using solid core wire is a huge no-no, and instead we opt for stranded wire with many many wires making up the strand.

So, if someone has the knoweledge, please explain to me why using solid core wire in an application that ranges from 5Hz up to many 10KHz ranges is preferred, let alone recommended.

 

Thanks! 

 

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I've seen many people recommend using solid core wire for their speaker cables. Now, speaking as an industrial maintenance electrician, I say this is absolute madness. Why do I say this? Skinning! The skin effect is very well documented. High frequency signal/power tends to travel on the outside or the skin, of the conductor rather than "saturating" the conductor. So in my world when dealing in VFD(usually up to 240Hz) applications, using solid core wire is a huge no-no, and instead we opt for stranded wire with many many wires making up the strand.
So, if someone has the knoweledge, please explain to me why using solid core wire in an application that ranges from 5Hz up to many 10KHz ranges is preferred, let alone recommended.
 
Thanks! 
 

I have read some similar opinions, but also have read it's highly NOT recommend (which I follow). I'm not interested in solid core. That being said, what's the word on marine grade type 3 tinned copper strand for speaker wire runs (especially to outside speakers)?


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Solid core wire read RG-6 read solid copper not copper clad steel was used by us for speaker and on more than one occasion for rca phono terminated for longer than usual runs.

Although stranded copper is used everyday for long runs, we wanted to make certain that after traversing a wall and fishing into the attic and going across and down into the other room, there were no firestop questions in anyone's mind. Copper clad is fine for certain applications but for marine of course, stranded is the path more traversed within reason,imho.

Thanks!

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Solid core wire read RG-6 read solid copper not copper clad steel was used by us for speaker and on more than one occasion for rca phono terminated for longer than usual runs.
Although stranded copper is used everyday for long runs, we wanted to make certain that after traversing a wall and fishing into the attic and going across and down into the other room, there were no firestop questions in anyone's mind. Copper clad is fine for certain applications but for marine of course, stranded is the path more traversed within reason,imho.
Thanks!

To be clear, the marine wire I mention is not copper clad, but copper stranding that is tinned. West Marine has a 50% off sale going on right now. Ancor brand. Looks to be nice stuff to me.


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Yes I read that and you appear to be in good shape, even overkill in my opinion but, if I had the coins, I would do it too.

Actually was trying to address any concerns or questions if any directed at the forum. from both of you.

Good fortune and happy boating...

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  • 2 weeks later...
On 7/18/2018 at 8:15 AM, alxlwson said:

I've seen many people recommend using solid core wire for their speaker cables. Now, speaking as an industrial maintenance electrician, I say this is absolute madness. Why do I say this? Skinning! The skin effect is very well documented. High frequency signal/power tends to travel on the outside or the skin, of the conductor rather than "saturating" the conductor. So in my world when dealing in VFD(usually up to 240Hz) applications, using solid core wire is a huge no-no, and instead we opt for stranded wire with many many wires making up the strand.

So, if someone has the knoweledge, please explain to me why using solid core wire in an application that ranges from 5Hz up to many 10KHz ranges is preferred, let alone recommended.

 

Thanks! 

 

 

Um er...    lots of words with no science to back it up. Yes to skin effect equations.  Yes, many high power power distribution also use flat conductors to reduce skin effects, but please use the *well documented* knowledge of skin effect in addition to basic electrical circuit theory including linear superposition and ohms law  to back up your claim in audio applications...  Perhaps a graph that shows skin depth vs frequency,  equivalent resistance vs frequency,  perhaps dB attenuation vs frequency..  You know the normal kinds of analysis used in the audio field.  I am not implying that skin effect does not exist but without numbers there is no way to tell if it really matters much.  PS last time I looked most speaker crossover inductor wire is solid.

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2 hours ago, efzauner said:

 

...........PS last time I looked most speaker crossover inductor wire is solid.

 

Ummm.  Apples vs oranges.  Different use of wire, but there ARE litz wire inductors  for HF. 

 

I would never recommend solid conductors for speaker wire. 

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6 hours ago, JohnA said:

 

Ummm.  Apples vs oranges.  Different use of wire, but there ARE litz wire inductors  for HF. 

 

I would never recommend solid conductors for speaker wire. 

why is there a difference, please back up your claim.   You basically have your speaker wire in series with the LF  inductor and the voice coil. lots and lots of solid core wire there... much longer than in many speaker cable runs.   What exactly is your recommendation based on? 

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The high voltage applications in our 100KW transmitters used tubular pipes to connect up the high voltage from the transformers as electricity (electrons) flows on the circumference (surface only). So if your wire is stranded you have more capacity because you have more surface area for current flow.

JJK

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4 hours ago, Deang said:

 

 

Thank you Deang!  That is a very simplified reduction of the math..

So a 12 gauge solid conductor at "75%" used at 20Khz would offer 33% more resistance than at DC.  

A 10 foot run of 12 gauge is 20ft x 1.6 mOhms per foot  that is 32 mOhms.... at DC

At 20Khz it would be about 43 mili ohms.  Not much difference I would say in series with a 8 ohm driver... 

I rest my case...

 

alxlwson   I am not questioning your claim about skin effect in high current power applications.  When currents are huge, the voltage drop and power consumed by resistance across feed cabling can be important compared to the power of the motor...  a 1% improvement in efficiency in a system is huge if you have to pay the power bills. 

 

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 I have used solid core for both interconnects and speaker wire. The stiffness is the biggest issue with the speaker cable. I think it does less damage to the sonics. And always unplated. Still have some solid core. Would be perfect for my Klipsch. Sixteen ga is fine.

  With interconnects, high purity copper wire in 24 - 26 ga is hard to beat. Gave in and use Canare Star Quad wire for my Klipsch.

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Continuing on this topic with the Belden data

If you use a stranded 12 gauge, there is still conductivity between strands so the skin effect would be somewhere between 0 and 33 % more resistance.  Certainly not 0. 

Unless each strand is insulated.... as in Litz wire. rather costly...  would be easier and cheaper to just go with a thicker gauge or 2 thinner lines. 

 

Yes LItz wire does what it is supposed to do. but I doubt it makes much noticeable sound difference. Sadly even with reasonable companies that typically makes good engineering choices based on real differences, our world of esoteric audio marketing has forced the use of litz wire inductors just because... customers have been conditioned to ask for it. 

 

Note that litz wire is mainly for higher frequency uses. not audio. 

 

https://en.wikipedia.org/wiki/Litz_wire

 

note that at 60Hz Skin depth is 1/3 of an inch..   at that depth the current density is 1/3  or about 1/3rd of what it is at the surface...   That is why in high power delivery they use flat conductors... 

 

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  • 2 weeks later...

@efzauner I made no claims to it being bad. I stated that my industrial electrician experience says it's a bad thing to use solid core conductor in higher frequency applications. I was looking for an explanation as to why that "best practice" is different in audio applications. 

Your second post was the answer I was looking for, rather than the condescending attack of your first post. I am not an engineer, I'm a motor controls tech, and a damn fine one. With that said, I hadn't really considered the fact that speaker wire isn't carrying much of anything, current wise. I deal with 480VAC and 250vdc, along with 4-20mA current loops, 0-10vdc bi-polar analogue control, etc... Audio is outside my realm of knowledge, and that's why I posed a question instead of a claim.

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On 8/15/2018 at 12:41 PM, Davis said:

When we were in Hope last year and speaker wire was the topic of discussion Jim Hunter looked at me and said "I just use Romex".

 

Don't you think he might have been pulling your leg? 🙄

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