Car wires are stranded for mechanical reasons. Wherever lots of vibration will be encountered, you should always use stranded wire. Vibration causes strands to break. No big deal if you have many strands, but if your one solid core breaks...
IMO, vibration is the biggest factor in deciding what to use. Something nobody talks about is insulation. If you're comparing wire, you're also comparing insulation, even if it's bare. There's capacitance to the chassis and to other wires- do you want that stray capacitance to be Teflon or do you like PVC capacitors? Any plastic insulation will have a higher dielectric constant than air. If you look in old bridges and HF test equipment you'll find a lot of very heavy bare wires for the point to point connections. I've no idea if this was for convenience or because it gave the lowest strays. I wire everything with stranded Teflon because it never retracts when you solder it and I figure it will far outlast me.
I'm still in newb amateur territory here, so sorry hadn't had much to add. But listening, lots of neat stuff.
One thing still turning up, sounds like either is usable; Some like one or the other, others are fine with both.
So it is answering my question. I mean there's been no "We all steer clear of such and such a type, it'll turn your amp into a useless white noise generator ..." or whatever general outcry.
Things have come a long way with wire knowledge and construction, sure sounds like. Must confuse a lot of novices, and others, when trying to decide what to use.
One thing still turning up, sounds like either is usable; Some like one or the other, others are fine with both.
So it is answering my question. I mean there's been no "We all steer clear of such and such a type, it'll turn your amp into a useless white noise generator ..." or whatever general outcry.
Things have come a long way with wire knowledge and construction, sure sounds like. Must confuse a lot of novices, and others, when trying to decide what to use.
Ya basically you choose the wire due to it's mechanical properties and insulation value.
As far as stranded wire being used in automotive applications because it's flexible is obvious. However you might notice the premium wires have a higher strand count, more then whats needed to make it flexible. It's science. Current runs around the OUTSIDE of the wire. The stranded wire will carry more current then the same size solid core. Things are rarely designed to be maxed out that way so you will rarely see an advantage.
As others stated use what makes sense to you in a given application. The most important rating is the insulation, make sure ALL the wire you use in a project enclosure has a voltage rating higher then the highest voltage seen in the unit. EVEN if it's carrying low voltage, still must be rated the same as the rest. 600v wire will get you through most tube projects,
As far as stranded wire being used in automotive applications because it's flexible is obvious. However you might notice the premium wires have a higher strand count, more then whats needed to make it flexible. It's science. Current runs around the OUTSIDE of the wire. The stranded wire will carry more current then the same size solid core. Things are rarely designed to be maxed out that way so you will rarely see an advantage.
As others stated use what makes sense to you in a given application. The most important rating is the insulation, make sure ALL the wire you use in a project enclosure has a voltage rating higher then the highest voltage seen in the unit. EVEN if it's carrying low voltage, still must be rated the same as the rest. 600v wire will get you through most tube projects,
Posts 11 and 17 claimed that skin effect was the rationale for stranded core conductors in 60Hz high amperage circuits. This is just plain wrong, because when they can use bus bar, they do. Stranded insulated wire is used for convenience and mechanical needs. While there may be a very small measurable skin effect, the choice of what type of conductor to use is not based on skin effect. You have claimed otherwise. You also mention in post 17:
Please explain how/why skin effect is significant at DC.
Full disclosure; I work with switchgear and isophase bus that is rated in terms of thousands of amps. "high amperage" is a subjective term; you would do better to quantify your claims of skin effect.
For most wires in most situations, most of the surrounding dielectric is air whatever insulation is used. You may have 0.5mm of PVC/Teflon/whatever then from there you have cm to metres (or kilometres) of air. Further out, on your way to infinity, you have vacuum.
I realise that the closer dielectric has the most effect, other things being equal. Scales with log of distance? In any case, it is at RF frequencies when dielectrics start to be a problem. Even if you did have a lousy dielectric at audio frequencies, you just have to drive the cable from a sufficiently low impedance and you won't notice it. And keep it short. The biggest problem, if it exists at all, will be people with 'high-end' preamps with far too high output impedance (or 'passive preamps') driving a long interconnect to their power amps by the speakers. If there are cable problems, then long interconnects are likely to do more harm than long speaker cables.
I realise that the closer dielectric has the most effect, other things being equal. Scales with log of distance? In any case, it is at RF frequencies when dielectrics start to be a problem. Even if you did have a lousy dielectric at audio frequencies, you just have to drive the cable from a sufficiently low impedance and you won't notice it. And keep it short. The biggest problem, if it exists at all, will be people with 'high-end' preamps with far too high output impedance (or 'passive preamps') driving a long interconnect to their power amps by the speakers. If there are cable problems, then long interconnects are likely to do more harm than long speaker cables.
I agree. The skin depth at 60 Hz in copper is around 5 mm. So for skin effect to matter to any significant degree, the wire would have to be at least 10 mm in diameter. Larger than most automotive jumper cables in other words...
Good one. One shall find angular frequency in the denominator of the equation.~Tom
Explain how you wire an amp using buss bar.
So you are aware of the "skin effect", yet you argue against it.
Tell me more because I'm real impressed.
The OP wanted to know if it was possible that a single conductor wire swapped to a stranded wire had an audible effect on sound, and it is indeed possible.
Nice try to redirect, but you have not answered the questions to any degree. I will answer yours when you answer my questions, which were asked first.
1. You claimed (posts 11 and 17) stranded wire is used because of skin effect in amplifiers, car audio, and the messenger supported wiring that feeds your house. This is false. If you want to continue to claim this, provide proof.
2. You claimed skin effect is pertinent at DC. Provide proof of this second false claim.
I fully understand skin effect; I don't argue against it- I understand when it is pertinent and when it is irrelevant. You are incorrectly applying the concept to attempt to explain someone's subjective opinion on sound improvement.
1. You claimed (posts 11 and 17) stranded wire is used because of skin effect in amplifiers, car audio, and the messenger supported wiring that feeds your house. This is false. If you want to continue to claim this, provide proof.
2. You claimed skin effect is pertinent at DC. Provide proof of this second false claim.
I fully understand skin effect; I don't argue against it- I understand when it is pertinent and when it is irrelevant. You are incorrectly applying the concept to attempt to explain someone's subjective opinion on sound improvement.
I've had to chop out some posts where the argumentation got personal. That makes work for me, which makes me cranky. Don't make me cranky.
I agree. The skin depth at 60 Hz in copper is around 5 mm. So for skin effect to matter to any significant degree, the wire would have to be at least 10 mm in diameter. Larger than most automotive jumper cables in other words...
~Tom
Which under accepted theory means that as frequency goes to 0 (DC) skin depth goes to infinety.
Using F.E. Terman's formulae to calculate wire diameter for 10% increase in ac resistance due to skin effect at 100KHz (picked as the highest practical frequency which could be realted to sound) yields 0.632mm.
Or roughly, 22AWG wire. This translates to a 1ft section of wire going from 16.1mOhms to 17.1mOhms.
Insignificant compared to the values we use for resistors, and the impedance of capacitors at the same frequency.
So at audio frequencies it is even less of an effect.
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