Power cables - am bewildered!

[arj]

Very interesting.

this should be easily explainable...I think Class ABs have an efficiency of around 50-60% so my 30W amp needs around 60W of steady state power...and dynamic instantaneous power need is around 2-3 times hence 120-180w which the regen could not supply

now if i had a 5-10 W pure Class A amp this would have worked perfectly

And I do not understand why isolation would make a difference, do you?

i dont know enough to comment. maybe as it has isolation transformers..which may filter out high freq RFI from coming in as well as not allowing High freq addition by digital equipment into the rest of the chain..
As before, not conversant with the details on the theory but it works and thats what matters in the end as its obvious when one hears

 

[sidvee]

Unfortunately in this forum you will get a small no of people with some experience who may or may not post and whole lot of people with opinions who will most definitely post

@ Arj you are on roll today:lol:, however you have nailed it, especially with this sentence, truer words have not been spoken. Apologies for the OT.
Cheers,
Sid

 

[doors666]

Has anyone connected a scope to the mains to actually make sure that there is garbage in there? Spending thousands of dollars to fix a problem that doesnt exist.

Most of the equipment works on dc, not ac. if the ac has any noise component, that also gets filtered away by the caps. so how will the garbage or noise make a difference.

It could make a difference to an equipment with a shitty power supply with inadequate caps, so if your equipment shows a difference, change the power supply, not the power cable. Same case with smps, many of them operate over 100-240v and give you a steady dc of whatever volts. how will the garbage in supply make a difference.

Please keep in mind that your audio equipment is actually just an electronics equipment

 

[arj]

...so if your equipment shows a difference, change the power supply,....

Hi..Did not understand this ..do you mean power source as in input power into the house or the ps unit of the component ? Either way not the least practical in my setup

 

[keith_correa]

this should be easily explainable...I think Class ABs have an efficiency of around 50-60% so my 30W amp needs around 60W of steady state power...and dynamic instantaneous power need is around 2-3 times hence 120-180w which the regen could not supply

now if i had a 5-10 W pure Class A amp this would have worked perfectly

But what is a real life listening scenario? Certainly not 30W, right? In real life you should be ~10-15W in which case there should be no issues, no?

 

[arj]

But what is a real life listening scenario? Certainly not 30W, right? In real life you should be ~10-15W in which case there should be no issues, no?

Maybe.. But as I said I am not really conversant with the theory..that was just a guess. Since I can hear the difference i just went with the optimized setup

Anyway was just sharing my experience and don't have the knowledge to justify it

 

[Thad E Ginathom]

Has anyone connected a scope to the mains to actually make sure that there is garbage in there? Spending thousands of dollars to fix a problem that doesnt exist.

Most of the equipment works on dc, not ac. if the ac has any noise component, that also gets filtered away by the caps. so how will the garbage or noise make a difference.

It could make a difference to an equipment with a shitty power supply with inadequate caps, so if your equipment shows a difference, change the power supply, not the power cable. Same case with smps, many of them operate over 100-240v and give you a steady dc of whatever volts. how will the garbage in supply make a difference.

Please keep in mind that your audio equipment is actually just an electronics equipment

Your response is somewhat in line with the "if the power messes with your equipment, you have bad equipment" line that I've heard from engineers. It is fair enough, and very much in line with rationality, which always appeals to me .

It isn't just India: wherever we go we'll find people complaining about the spikes and the brownouts, and about how even a slight consistent over-voltage can damage equipment. It isn't just from the audiophiles either. But I do think that we get it far worse in India, or at leasts parts thereof. for instance It would never have occurred to me to buy a UPS at home when I was in London!

I don't need any convincing that irregular voltage is not good, even if it is not audible. I'd be very happy to hear from an electrical engineer on the other aspects, but that is not in the negative sense: I'd just like more information on it.

arj's solution isn't thousands of dollars --- although I'm not sure that I share their definition of $850 as low lost :lol:.

On the other hand, even fifty years ago, when my parents were having heaps of trouble keeping a TV working properly, the engineers put recording equipment on the mains supply to check it out. No, there's no harm in real diagnosis and measurement. Mind you, I wouldn't have a clue where to start, and, even if I had one, would probably blow up the scope


.

 

[arj]

although I'm not sure that I share their definition of $850 as low lost :lol:.

:

nope its not..but a far better exchange rate in those days and great deal on the shipping/customs/final price made this worth far better than the only other option i had ie the APC/Leibert online UPS

todays exchange rate, i might not have gone for it.

 

[Thad E Ginathom]

Always happy to argue against myself :lol:

I mentioned (twice) the thing about power supplies being supposed to do their job.

OK... so why do many companies offer us upgrade power options? Power supplies that do the job better?

I certainly have an experience of power configuration making a difference. I was listening with DrBass. He said, "something's not right," Jumped up and changed some stuff. I did not even know what, but yes, I could certainly hear that the sound had changed. It turned out that he had actually removed the Naim power supply. I did not follow the reasoning, but I can take it as personal proof that power supplies change things.

Topic slipping here, from power chords, to conditioning/isolation, to power supplies.

 

[kanwar]

If power cable makes a difference then the power supply of the equipment is a piece of crap.

Some 'designers' who cannot design a capable power supply or an audio circuitry advise their customers to live by the garbage coming out of the speakers. So changing power cables or tweaking the power supply can "Affect the Sound" in either way.

 

[jls001]

Everything else being equal including good S2S contacts, if I used Al plugs as opposed to Copper or Brass - would they make a +ve sonic/audible difference? If yes, why?

Not that I know the answer to post # 1, but Al plugs are not used because they are much worse conductors of electricity than brass or copper. Mechanically too, Al is weaker than brass or copper. In fact the most widely used material is brass plated with chrome or, in some cases, rhodium. But raw copper is the better conductor. If one were to believe marketing spiels, oxygen free copper is better than plain old copper. And if one were to believe them even further, the purer the copper, the better they are as conductors. And if one is lucky enough to get hold of copper drawn by the method invented by Prof Ohno somewhere in an university in Tokyo, you will be blessed with extra long crystals which are superior to other types of coppers.

Copper is, however, not widely used in its raw form, mainly because of one disadvantage - it oxidizes (IIRC, verdigris is the term). Gold-plating a copper connector is therefore not only about aesthetics but a necessity as well. But if you open an electrical distribution panel, they use thick copper strips as bus bars, and not of aluminium or iron.

And the above is an "opinion" piece

 

[jls001]

Good article: Audio Power Cables & Cords - Do they really make a difference? | Audioholics

Please read both pages.

 

[Thad E Ginathom]

Audioholics/Blue Jeans Cables

 

[Santy]

Nice article there.
Most of it emphasize that the thickness of the cord as an important criteria.

I have a few observations:

It initially says that an under-gauged wire may not be able to deliver the current the caps need while playing bass-heavy music (considering the PS is not well-designed)
But later it says a wire designated for 14 amps can pass "a lot more" current than it is designated to, until it melts.
So if the power cord dosen't melt while listening, it means it is able to take care of the current requirement just fine.
Eventually the article sways into electrical safety than aural differences the gauge specification makes.

Whatever, I liked the paragraph on Exotic cables.
Blind testing only can tell if they make a difference.

Theoretically every physical piece in the gear could affect the sound. Just like how a butterfly can trigger a Tsunami. But how much the system can reveal or how much we can perceive is the question.

 

[captrajesh]

yup..they make no difference so no sense arguing or wasting your money.

better to read than start our own thread where nothing fruitful comes up

After reading the thread title, I was hoping (against hope:lol that a non believer has turned to believer after getting down to doing his own testing and was truly "bewildered"

Alas, that was not to be. Sigh :sad:

 

[arj]

.. But how much the system can reveal or how much we can perceive is the question.

And therein lies the problem. if the system is itself not resolving enough, that could also be a reason for no differences.
..and its not necessarily a bad thing, if the music is still enjoyable to ones ears thats all that matters

 

[jls001]

A very technical article from Sound Stage for those inclined: SoundStage! Pete's Place - JPS Labs Superconductor Interconnects: A Technical Discussion (09/1998)

 

[Thad E Ginathom]

Thanks, I'll look. There's another really good article on what does and does not make a difference in speaker cabling, from the MacIntosh (Mac? Mc?) guy --- but the last time I mentioned it someone decried it as being old, as if that makes a difference.

After reading the thread title, I was hoping (against hope:lol that a non believer has turned to believer after getting down to doing his own testing and was truly "bewildered"

Alas, that was not to be. Sigh :sad:

Nope. It's the other way around for me! I did by an exotic power lead once. I still use it, because it's there. I guess I "heard" some difference at the time, but I now think, no, I don't. And, what's more, the grip at the amplifier cable is inferior to the normal mass-produced computer cable.

...later it says a wire designated for 14 amps can pass "a lot more" current than it is designated to, until it melts.
So if the power cord dosen't melt while listening, it means it is able to take care of the current requirement just fine.

I'm not sure about that. It takes a certain amount of current/time to build up heat to melting point, whereas the peaks in music are going to be very fast. It takes time to blow a fuse (unless it is designed to be quick blowing). Therefore there might be a case for resistance affecting those peaks. But surely this could be measured really easily and is hardly worth applying ear time to argue --- but that wouldn't suit cable companies and those who "buy" what they say.

Of course, when it comes to stuff melting, the insulation is going to break down and catch fire long before the metal melts. Melting metal is, perhaps, poetic licence! My not-particularly-special speaker cables are certainly thicker than any house wiring I have, but I think that mains current would reduce them to a nasty, sticky, burning, poisonous mess.

 

[Santy]

Of course, when it comes to stuff melting, the insulation is going to break down and catch fire long before the metal melts. Melting metal is, perhaps, poetic licence!

Yeah but that is what the article claims, that if low gauge cable is used, it might melt (though I think it is the insulation that is being referred to). I also don't think anyone would make a power cord as thin as a earphone wire for an amplifier. rolleyes:

People sometimes make the mistake of thinking of the power cable as limiting the current available to the device it feeds in an absolute sense--that is, as though a power cord designed to take 14 amps will take 14 amps and no more. In fact, the limitations upon amperage, often referred to as "ampacity," which we see marked on products or in spec sheets are not absolute limits--it is, indeed, possible to push a tremendous amount of current through a 14 AWG wire, up until the point when the heat generated melts the wire and breaks the circuit (the "fusing" current).

Even insulation melting and/or catching fire due to loud music played on a system is . Well, I don't know, may be possible with powerful class A amp, driven using some low gauge power cord as warned by the author hyeah: But I am sure the manufacturers of hifi equipments have some basic idea about the maximum current their product will consume, that they would certainly not leave it to the consumer to figure out if they need a thicker cord.

 

[Thad E Ginathom]

I also don't think anyone would make a power cord as thin as a earphone wire for an amplifier.

OK, so a bit of poetic licence from me there. It wasn't for an amplifer, but some low-power device --- but it was so damn thin I could not easily strip the insulation to change a plug.

Even insulation melting and/or catching fire due to loud music played on a system is

Who's got the highest power amp? Shall we try it? :lol:. The HiFiVision Speaker Cable Burn Up Challenge!. Someone bring an amp, someone bring a foam fire extinguisher...

I wonder if it might just be possible if we tightly coil the cable? hyeah:

But no, I wouldn't risk shorting out my amplifier either!

Oh, wait, you're talking power cords...

But I am sure the manufacturers of hifi equipments have some basic idea about the maximum current their product will consume, that they would certainly not leave it to the consumer to figure out if they need a thicker cord.

The one they supply! I was actually quite surprised that my 40-watt-output Cyrus came with a 15-amp plug/cable.