[transam]

I'm looking at upgrading my power cords.Do i need to replace power cord on my speakers,cdp,pre,amp?I'm looking at virtual dynamics basic power it looks like a great cord.Thanks for the help.

[DVV]

I'm looking at upgrading my power cords.Do i need to replace power cord on my speakers,cdp,pre,amp?I'm looking at virtual dynamics basic power it looks like a great cord.Thanks for the help.

Changing power chords from the usual run-off-the-mill we get with most audio most often yields good results. Since that chord uses a conductive material, usually copper in some version, it naturally has its own RLC characteristics.

When you swap the regular stuff with some decent OFC power chords, the input impedance, inductance and capacitance on your equipment is changed for the better, hence the improvement in sound. Your audio quite simply is now able to draw power more easily.

The greatest difference will always be on what draws most power because that's where the greatest problem always is - meaning your power amplification. But other components will also react, perhaps not as much, but still.

Go for largest cross section for lowest impedance. There are many to choose from, and almost all promise miracles. Don't expect miracles, but there will be a change. Try with the power amplification first, then move on elsewhere, in steps, so you can determine the differences.

If you can, go for chords which have their conductors wrapped in oiled paper, then some insulation. Natural rubber is best, but quality plastics will also do fine.

Cheers,
DVV

[Ernest]

Don't expect miracles, but there will be a change.

This is such great advice!  So often this is exactly what happens.  I expect a big change but get something subtle but real (and worth having).  This should be standard advice for audio newbies.

[audioengr]

DVV - Transam is correct.  I have found that with most customer systems, the power amp is the most sensitive to power cord change.  I have my own theory as to why this is the case:  The inductance is the issue.  Here is a technical explanantion and an example:

Amplifiers demand current from the power-line when the capacitors in their power-supplies become momentarily discharged due to high-current transients in the music signal. This discharge condition must be quickly recharged from the power-line, through the power-supply transformer, or a voltage sag will occur. Such voltage sags can cause audible distortion at the loudspeakers. If the power-line has significant series inductance in the path from the power panel to the amplifier, this can prevent the capacitor bank from recharging in time to prevent a voltage sag from occurring at the amplifier output transistors. With a low-inductance cable, the voltage drop across the cable will be insignificant during high-current transients, minimizing the voltage sag. This allows all of the current needed by the output transistors to be supplied when they need it, resulting in  fast, dynamic response to transient signals.

A typical 6-foot 14 AWG rubber cord and 25 feet of ROMEX has inductance of 7.2 uH and resistance of 235 mohms, ignoring the plug resistance effect.  Therefore, the voltage drop at 20kHz will be I*(wL+R)= I*(.905+.235) = I*(1.14).  With a 6-foot Magnum2 and 25 feet of ROMEX, the inductance is 5.9 uH and the total resistance is 147 mohms.  This is an 18% reduction in inductance and a 37% reduction in resistance.  The voltage drop for this combination will be I(wL+R) = I(.741+.147) = I(.888).  So at a fixed dynamic current I, the voltage drop in the entire power feed at 20kHz is 22% smaller with a Magnum2 power cord.  I would consider 22% to be significant.  The reality is even more compelling.  When you add in lower plug and receptacle resistance and the fact that the di/dt on the power cord will have spectra well above 20kHz with some amplifiers, the low-inductance cord makes an even bigger difference.

[DVV]

DVV - Transam is correct.  I have found that with most customer systems, the power amp is the most sensitive to power cord change.  I have my own theory as to why this is the case:  The inductance is the issue.  Here is a technical explanantion and an example:

Amplifiers demand current from the power-line when the capacitors in their power-supplies become momentarily discharged due to high-current transients in the music signal. This discharge condition must be quickly recharged from the power-line, through the power-supply transformer, or a voltage sag will occur. Such voltage sags can cause audible distortion at the loudspeakers. If the power-line has significant series inductance in the path from the power panel to the amplifier, this can prevent the capacitor bank from recharging in time to prevent a voltage sag from occurring at the amplifier output transistors. With a low-inductance cable, the voltage drop across the cable will be insignificant during high-current transients, minimizing the voltage sag. This allows all of the current needed by the output transistors to be supplied when they need it, resulting in  fast, dynamic response to transient signals.

A typical 6-foot 14 AWG rubber cord and 25 feet of ROMEX has inductance of 7.2 uH and resistance of 235 mohms, ignoring the plug resistance effect.  Therefore, the voltage drop at 20kHz will be I*(wL+R)= I*(.905+.235) = I*(1.14).  With a 6-foot Magnum2 and 25 feet of ROMEX, the inductance is 5.9 uH and the total resistance is 147 mohms.  This is an 18% reduction in inductance and a 37% reduction in resistance.  The voltage drop for this combination will be I(wL+R) = I(.741+.147) = I(.888).  So at a fixed dynamic current I, the voltage drop in the entire power feed at 20kHz is 22% smaller with a Magnum2 power cord.  I would consider 22% to be significant.  The reality is even more compelling.  When you add in lower plug and receptacle resistance and the fact that the di/dt on the power cord will have spectra well above 20kHz with some amplifiers, the low-inductance cord makes an even bigger difference.

All very true - I was trying to evade the tech talk and keep it on a level everybody can understand. But what you said above is all quite so.

Oddly enough, even some mid-market manufacturers are aware of this. For example, my Harman/Kardon 680 integrated amp (now discontinued, never available in N. America) has a VERY thick cable, way out of the ordinary junk they usually install because it's cheap. But then, it's all made out of the ordinary, from a 500 VA E-core transformer of very good quality, to double rectifiers per channel (each supply line has its own full wave bridge rectifier), to a true dual mono construction and Elna filter capacitors. So, it can be done for even reasonable money, I paid about $900 for it in 2000.

But while I am aware of the cable problem, I'm also disgusted at the kind of nonsense, myth and magic people are being handed by cable manufacturers. Such as miraculous benefits, just lay your $xxx down and man, it's nirvana in a jiffy!

The only nirvana I have known for a three figure number was my DeZorel line filter, which sounds the pants off anything else I tried, and since it's the only thing that ever did that to me, I conclude it's the odd man out, not the rule.

And now that you mentioned it, a good line filter will also much improve power supply efficiency, far more than a good cable - but together, now there you really start hitting nirvana levels.

Cheers,
DVV

[Xi-Trum]

Some amps come with *captive* power cords, i.e. power cords that are permanently attached (welded) to the amp at one end.  In effect, the power cord is an extension of the power supply.  For the experts out there, what are the benefits (pros/cons) of having the power cord as part of an amp?  Technical reasons?

Thanks.

(Sorry if this is off-topic a little bit)  

[Dan Banquer]

A while back I measured thre input inductance of some of my power transformers and found that they measured 50 Henrys on the transformers I use in the LNPA 150's. This inductance is across the AC line. I would greatly appreciate it if someone would enlighten me as to how a few micro-henry's of inductance in a line cord would make any substantial difference.

[DVV]

A while back I measured thre input inductance of some of my power transformers and found that they measured 50 Henrys on the transformers I use in the LNPA 150's. This inductance is across the AC line. I would greatly appreciate it if someone would enlighten me as to how a few micro-henry's of inductance in a line cord would make any substantial difference.

For this to make a world of difference, Dan, you have to fulfill just one condition - you have to be in the cable business.

Larger cross sections I can understand, lower impedances even, but inductance in a power chord?

But then, I'm not in the cable business either.

Cheers,
DVV

[nathanm]

...Go for largest cross section for lowest impedance...

What do you mean by cross section?  The guage of the wire?  Is heavier guage\more copper better?  

What I don't understand is how come I can go to just about any hardware store and get household wiring for a few cents a foot, but the store-bought "audiophile" grade cables cost hundreds, even THOUSANDS of dollars?  Isn't it all just copper?  Is the hardware store stuff not oxygen-free enough? Sure, it costs money to have folks assembling cables, but why in the world do people spend hundreds on basically a few variations on a theme: X amount of copper, XYZ type insulator etc.

If I make my own big fat power cord for 30 bucks what makes it any different than something I bought from, let's say Boulder, for 300?  I'm not arguing about sound, or wether or not I can hear a difference, I'm talking about the bill of materials.  Where does the money go?

[DVV]

...Go for largest cross section for lowest impedance...

What do you mean by cross section?  The guage of the wire?  Is heavier guage\more copper better?  

That's it, Nate. The more copper, the more current, it's as simple as that. I'm not saying all wires are of the same quality, which will also play a significant part, but only up to a point. A 2 mm thick super duper extra special wire will still not be able to compete with a hick 10 mm thick copper wire in terms of passable current.

What I don't understand is how come I can go to just about any hardware store and get household wiring for a few cents a foot, but the store-bought "audiophile" grade cables cost hundreds, even THOUSANDS of dollars?  Isn't it all just copper?  Is the hardware store stuff not oxygen-free enough? Sure, it costs money to have folks assembling cables, but why in the world do people spend hundreds on basically a few variations on a theme: X amount of copper, XYZ type insulator etc.

If I make my own big fat power cord for 30 bucks what makes it any different than something I bought from, let's say Boulder, for 300?  I'm not arguing about sound, or wether or not I can hear a difference, I'm talking about the bill of materials.  Where does the money go?

Sexy packaging, distributorships, marketing, ads, etc. If the boss happens to like that his secretary should wear Parisian black lace panties, then the cost of that too ("creative accounting"). True, some of those cables really do cost a bit to make, but find the original manufacturer, like http://www.neotech.com.tw and marvel at their prices versus what you are asked to pay under one famous name or another.

Cheers,
DVV

[Dan Banquer]

Nathan; You can buy shielded power cords at either 18 AWG, 16 AWG or even 14 AWG from any number of places for under $10.00. Try www.jameco.com

[DVV]

Some amps come with *captive* power cords, i.e. power cords that are permanently attached (welded) to the amp at one end.  In effect, the power cord is an extension of the power supply.  For the experts out there, what are the benefits (pros/cons) of having the power cord as part of an amp?  Technical reasons?

Thanks.

(Sorry if this is off-topic a little bit)  

The Harman/Kardon 680 I mentioned as having an uncommonly thick power cable also uses captive. I didn't change it, I got it like that from them.

As for the benefits of captive power chords, one less set of contact points DOES make a difference, if nowhere else, then on the bench desk. Less chance of dirt and grime settling in and spoiling the show, one set less chances of somewthing going wrong or becoming unstuck or unreliable, and one less crossover impedance in the whole game.

You guessed it - the less, the better.

If you must have a joint, try your best to make it a solder joint. Any joint is trouble and junk, but sodlered joints least of all; hence, lest evil is best.

Cheers,
DVV

[Hantra]

Sexy packaging, distributorships, marketing, ads, etc. If the boss happens to like that his secretary should wear Parisian black lace panties, then the cost of that too ("creative accounting"). True, some of those cables really do cost a bit to make, but find the original manufacturer, like http://www.neotech.com.tw and marvel at their prices versus what you are asked to pay under one famous name or another.

Although this quote was likely designed to ignite flames, I am not going to be the one to get it started.  I will say that I disagree with you that all cable manufacturers are this way.  While I only have personal knowledge of two cable manufacturers' business practices, and research practices, I will say that you are wrong in collectively bashing all cable manufacturers.

Things like quarter million dollar network analyzers, test facilities, and kilovolume research libraries are not free.  Hundreds of thousands of man hours worth of research is not free.  Labor is not free, and I can tell you from my own knowledge that it takes quite a bit more than most people think to terminate a cable, and do it RIGHT.  

I'm sure a Taiwanese company can do it well, but their idea of quality control is to pull a cable off a palette of 25,000, and test it.  If it works, then let them all rip.  That's not how it is done at a real cable manufacturer.  In a real shop, each cable gets terminated individually by people who know what they are doing, and actually are staking their name, and that of the company on how good a job they do.  These Taiwanese bulk manufacturers don't give a crap if 10% of their stuff is bad with crappy termination.  They don't likely spend hundreds of hours designing dies to extrude light gauge copper without using lubricant to pollute the structure of the copper.  

I don't know man, from what I have seen, your assessment of the industry is way off.  Manufacturers like Monster, or Transparent likely are bankrolling Parisian lace panties for the staff, but the real manufacturers out here like Kimber, Cardas, and guys like that are busting their asses to get the patents and compete in a very tough business.  Small guys like Bolder, and like Empirical also work very hard, and are not out to kill anyone with their pricing.  Although I have not heard the Empiricals, Wayne makes a hell of a cable for the money!

I won't disagree that guys like Kimber, and Cardas are making lots of money, and have nice margins.  That's what my country is all about though.  If you have value to provide to others, then you make money.  You only make as much as the value that you can provide to your fellow man, unless you are a CEO of a publically traded corporation.  Last time I checked, there weren't any real manufacturers that were public.

DVV, as a manufacturer, would you be okay with others saying the same about your business practices?

B

[Danny Richie]

The differences power cords can make was really made clear to me over a year ago when I tried spme cables that a buddy of mine produces.

He had a couple of different ones.

His MPC 14 improved low end response without question.

His MPC 12 not only improved bottom end response but really improved imaging as well. Everything had a more airy layered sound with a clear sense of distance between instruments, etc. Sound stage was deeper, bigger, wider, and all that too.

I was so impressed I purchased larger quantities of them and have been reselling them for him.

These things go through a number of treatments from mechanical to heat treating to cryo treating.

The MPC 12 sells for $225. each. Not cheap, but still far cheaper than many other similar cables.

I don't want it to sound like I am trying to make a sale here or anything, but I did feel it necessary to give you all info so you can take it for what it is worth.

How much difference does it really make and is it worth it? I let my customers decide.

Upon request I send one out as a sample.

I sent one out to Jackman last week.

Try it yourself to see what difference it makes. Review it or not, keep it or not, it bothers me not.

It only cost a few dollars to ship it back or to the next guy. It is only a power cord. It doesn't weigh much. US mail handles it fine.

Be for warned though that about 80% of those I have sent out never come back. Most feel they must keep them. Several wanted to keep them, but could not afford them. So if you can't afford $225. for a cable you might wait until you can to demo one.

Many put them on everything in the system as I have.

Believe it or not it has been found to make more difference in CD players and or DAC's the most, phono pre-amps and line level pre-amps next, and power amplifiers last.

[EProvenzano]

Here's my two cents...(please add appropriate disclaimer here)
When I can DIY a cord that is 99% of a commercial cord that costs 4 times the price, it's a no brainer for me! Someone else can pay for all the marketing, R&D, etc. I've got more important places to put my money...like buying more music.
I am not saying that a good PC is not worth the money relative to other components. I have indeed heard a good PC make significant improvements to my sound system. However, commercial cords are grossly over priced relative to what anyone can DIY.
EP

[DVV]

Hantra,

You may not have seen that comment, but for the last 15 years or so, I've been saying, and I now say it again - real audio lives at the outskirts of the industry, with the small guys.

What I have said about the cables stands as far as I am concerned, but I do agree I missed that famous "but", and I shouldn't have. Mea culpa.

I agree not all manufacturers are the same; I agree some, albeit a minority in overall terms, take pride in what they do and really, honestly care about their products and customers. It's these people who keep real audio alive, not the run-off-the-mill stampers, though they too are needed.

Best of all, or so I think, over the last few years we seem to have been greeted by a growing number of small guys, who are really trying to do something worthwhile. Whether they make it or not, whether I agree with it or not, is really beside the point - they are honestly trying.

But whether you agree with it or not, they all make up like 5% of the overall industry, which, as any modern indistry, is really concenrned only with the sales figures, dollars and cents. The sad truth is that over a certain point, companies change their credo, at least in most cases.

And I am not trying to be inflammatory, I'm sorry if you took it to be so, I was really only speaking my mind. I am (too) well acquainted with that industry, and I see just how much dirty laundry it produces. From real price lists of well known names appearing in magazines, to various swindles (that's what I call it when you promise things you KNOW you don't, and often can't deliver, to justify a mad price tag).

Yes, my view of the industry is a bleak one - but that's not to say all is lost, nor is it meant to say nobody is even trying. Fortunately, there are still those who are really trying.

Cheers,
DVV

[DVV]

Here's my two cents...(please add appropriate disclaimer here)
When I can DIY a cord that is 99% of a commercial cord that costs 4 times the price, it's a no brainer for me! Someone else can pay for all the marketing, R&D, etc. I've got more important places to put my money...like buying more music.
I am not saying that a good PC is not worth the money relative to other components. I have indeed heard a good PC make significant improvements to my sound system. However, commercial cords are grossly over priced relative to what anyone can DIY.
EP

Now you hit the nail on the head - value for money. THAT'S what I am talking about.

The problem with most add-ons is that they are overpriced. They do make a difference, but not as large a difference as you are expected to pay for them. Note I said "most", not all.

What's to stop you from buying some decent cable, having it cryogenically treated (costs about $20-25, I am told), put on a really good quality plug, and have a super power cable for less than $100? You won't have a famous name, or sexy packaging, you won't be able to impress those who are impressed by name and especially price tags, but you'll still have a great power cable.

True, a manufacturer does have very real costs he has to cater for, but then he buys bulk and from the manufacturer, so his cable comes much cheaper than yours bought in a retial store. His cryo will average out at about $10 per power cable because he doesit large scale, and that plug you bought for say $25, he'll pay something like $10-12 for it in bulk, from the original manufacturer.

So, if he asks say $150 for it, I'd seriously wonder whether it's worth my while to fool around with it all, and would probably buy it. But if he asks say $300 and over, I'd tell him what to do with it, go out and make my own. He just walked clean out of the value for money zone as far as I am concerned.

But what can you expect in a business where the distributor wants to make no less than 25% on it, and the typical dealer won't even talk to the distributor for a margin smaller than 30%, often 40%? Add shipping costs, advertising costs, taxes, duties and a multiplication factor of 2.7 over the original price starts to look reasonable.

Here's a real world example. Karan Acoustics, a local high end manufacturer, ask for $1,900 for their integrated amp on the local market (2x180/250W into 8/4 ohms), but this same amp costs $5,600 in the US. A factor of 2.95, no less. At $1,900 it's a steal, but at $5,600 I'm not sure I like it enough to pay for it.

Cheers,
DVV

[Hantra]

DV:

Thanks for the clarification.  I agree for the most part with your outlook.  It is an industry with only a couple hundred thousand potential customers, and I am sure everyone is looking to generate more of them.  But that won't happen until we get more people closer to the music, and not just the pretty gear and cables. . .

B

[nathanm]

Yep, I kinda figured I'd be opening a can 'o worms with that post!  

Seems like if you spend a little bit of money you can make cords that look just as nice as the store-bought stuff.  Shrink tube and expandable sleeving - that seems to be the key for the looks part.  The sleeving also makes them slippery so they are easier to yank through a rat's nest of cables.  I rather enjoyed making my own speaker cables, even though it was indeed a fair amount of work.  If you get solderless plugs then it goes quicker.  Maybe I'll have to make some power cords next.  Those plugs can still be rather steep.  Those German WBT connectors certainly look full-ass, but 44 bucks for a single RCA plug?  I think I feel faint...must sit down...

[DVV]

Yep, I kinda figured I'd be opening a can 'o worms with that post!  

Seems like if you spend a little bit of money you can make cords that look just as nice as the store-bought stuff.  Shrink tube and expandable sleeving - that seems to be the key for the looks part.  The sleeving also makes them slippery so they are easier to yank through a rat's nest of cables.  I rather enjoyed making my own speaker cables, even though it was indeed a fair amount of work.  If you get solderless plugs then it goes quicker.  Maybe I'll have to make some power cords next.  Those plugs can still be rather steep.  Those German WBT connectors certainly look full-ass, but 44 bucks for a single RCA plug?  I think I feel faint...must sit down...

Or you can say pretty please with sugar and honey on it, and I can send you RCA plugs which are the same as Neutrik, minus the Neutrik name, but from the original manufacturer, who is (guess what???) from Taiwan. And that they are the one and the same I verified in a rather good lab - literally identical. Except in price, of course.

Do I use them? Of course I do, they are really good RCA plugs, BUT only at the price I pay for them, not at the Neutrik price.

Cheers,
DVV