How does length affect power cable sound quality?

I've read that longer is better [ well just ask the ladies :-) ] but seriously now...
Why longer lengths are considered to sound better I don't understand, but that's how those who have experimented have answered this question. I recall that it does relate to the filtering action of the longer length being more effective. How much longer & how much difference(?) is better answered yourself, in your own rig, with a particular cord connected to a particular component. Order a 6' length of Power 3 for comparison sake would be my suggestion. Any other cable, of any other length, in any other rig, is not necessarily legitimately comparable with your own results.

Unless you are talking about an extremely long run of power cable, or a cable with really bad quality wiring and/or construction, there should be no audible difference between a 3 foot and a 6 foot length.

Consider that the power coming from your wall socket has just completed a trip of hundreds, maybe even 1000 miles or more, and gone through how many switches, transformers, etc., and the distance from your outlet to your audio system pales in comparison.

I have tried various lengths of power cords and so far it appears that six feet to ten feet sounds best. A reviewer and an audio shop owner have told me that the better power cords are designed to dampen/filter "mechanical" resonances, amongst other things. And that if the cord is too short (less than six feet) it is physically unable to accomplish this purpose. One designer used an analogy of comparing a power cord to an attachment you put at the end of a garden hose in that both change the character (focus/filter, etc.) of the what comes out at the end.

Therefore, it does not matter how many 1000s of miles the electricity goes through before it gets to your outlet- it is the last six to ten feet that really counts.

OK- here's what I understand so far: A power cord designed for the purpose of altering the perceived sound quality is usually best at a length of 6-10 feet.
So do quality power cords work in conjuction with power filters? I'm currently running Monster Power HTS-2000 for my Stereo rig, and a Monster Power HTS-5000 with a Monster Power HTS-1000 plugged into it for my Home Theater. I also have 8 AudioPrism Quiet-line Filters stategicly placed.

I guess the answer in in the hearing. It seems to me that power filters should clean things up so that further filtering with a 10-foot power cord would be redundant. But my ears say this isn't so.

Maybe what I'm asking hear is WHY does a quality 6-10 foot cord make a unit sound better. I'd like an answer with all the physics involved fully explained. The point is that if it were possible to mathematicly describe why one piece of equipment sounded better than another, it would be easy to just design it. But it's not, because there is too much magic involved. (Magic, or voodoo, is just another term for science that no one understands.)

There's a couple of people you can call for an answer and I'm sure they'll help you:

1) George Tice (www.ticeaudio.com)
2) Bill Parish (www.gttgroup.com)

Tice's line conditioners include a fixed TPT treated power cord--which *does* enhance the musical signal. Bill Parish markets the Absolute Power Cord, which was designed to be tuned exactly at a length of 8 feet.

I think this is what's happening with Tice's treatment:

Electricity exhibits the behavior of both wave and particles. So what's in the conductor as impurities will cause particle collisions and the way the lattice is arranged will also influence the wave/particles. TPT treatment rearranges the lattice--it's a materials treatment, like cryogenics. One works by tempering, the other uses voltage/magnetic field manipulation. And Tice uses *the* best copper available--he's a fanatic!!! What's going on, in my layman's opinion, is that TPT in conjunction w/ Tice's top quality copper sends a very unique waveform to the electronics. And that waveform is indeed the raw material from which music is made...

I had some 3 foot and 6 foot Vansevers cords of the same make. The 6 foot cords were a little warmer to my ears. I also found at least 6 foot was best for my REL sub. I have some other brand cords, but only in 6Ft or more, so can only speak about the VE cords.

Since some cords use specific geometries to achieve desired impedance characteristics, it is possible that altering length could alter their overall performance. With that in mind, doubling the length of a cord could double the effective capacitance. In a reverse situation, using a cord that was half as long would cut the capacitance by 50%. Same can be said for inductance too. Whether or not this would come into play at all would vary from system to system and location to location.

Another factor that could come into play is susceptability to RFI. A longer cord makes for a better antenna. As such, if you're going to run long cords, make sure that they have adequate shielding or take advantage of geometries that offer "natural" shielding to RFI.

Also make sure that you're using a cable that is heavy enough for the device that it is connected to. Whereas an 18 gauge cord might be fine for a CD player, tuner, etc... it is not suitable for any reasonably sized power amplifier. Sean
>

In systems like the power feed or amplifier feeds, the output impedance of the power source is very low. Because of this, the capacitance between the two conductors is not important. The series inductance is important because current transients that surge through the wires will meet with extra resistance due to the inductive reactance. This will create a transient voltage drop over the length of the cable. For instance 117VAC becomes 116ACV momentarily. The length of the cable is proportional to the inductance. Longer cable, more inductance.

In the case of the power cord to a power amplifier, anything that limits the current inrush that would normally recharge the amplifier power-supply capacitor bank after it is momentarily discharged, can cause a voltage droop at the power output transistors. Any significant momentary droop at the output transistors can cause audible distortion. You can think of the capacitor bank as both a filter to eliminate 60 Hz (to create DC) AND a battery of sorts that stores DC power potential to be expended when the power transistors demand it during high-power transients. When high-power is demanded, the capacitor-bank (battery) actually depletes, the voltage at the transistors eventually dropping as a result. To counteract this, the rectified AC power directly recharges the caps every half-cycle when the recitifiers are conducting. If the power-cord is inductive (as most rubber cords are), then this recharging action can be limited. If there is no high-current demand from the music, the caps just get charged initially and then very little additional current is drawn from the AC power cord.

A 20ft cable would be fine right?

I use and enjoy 5 meter powercords, have several, and some 4 meter ones too. I also have the same brand 1 meter cords, 2 meter cords.. I DO move them around ,and have swapped longer shorter, fatter, thinner... Sometimes the sound changes a little. Sometimes not. I used to need to use 4 meter pC, and I thought they helped. Now with the same brand in two meter or even one, no change.I am using a power conditioner also. However using larger gauge even on source or preamp may change the sound a bit.

I use and enjoy 5 meter powercords, have several, and some 4 meter ones too. I also have the same brand 1 meter cords, 2 meter cords.. I DO move them around ,and have swapped longer shorter, fatter, thinner... Sometimes the sound changes a little. Sometimes not. I used to need to use 4 meter pC, and I thought they helped. Now with the same brand in two meter or even one, no change.I am using a power conditioner also. However using larger gauge even on source or preamp may change the sound a bit.

Wow how do you have time to write here with all that power cord experimentation going on? 

Well, there are plenty of seconds in a minute. and sixty of those in an hour. With an average of 16 hours available a day. Being retired that is 365 days a year. And I have been playing around with power cords at least since 1998.. Twenty years, (that includes at least 4 leap days) times 365 days times 16 hours a day... etc means I have had 420,710,400 seconds of time available, and somewhere in there I spent a few of them moving around powercords. I am positive have spent far more time wiping my behind than moving powercords around. But less time doing that than posting around here and other audio sites, since here alone I have managed to whittle away at nearly 6,000 meanderings. You on the other hand, with 95 posts, have certainly been wiping you behind way more than posting...

BAM!!!  Nicely done Elizabeth!

Wow, discussions here can get nasty in a hurry...
Roger, I must say you asked for it...

5 or 6 feet is optimum longer than 10 feet is not great.

 

Well, there are plenty of seconds in a minute. and sixty of those in an hour. With an average of 16 hours available a day. Being retired that is 365 days a year. And I have been playing around with power cords at least since 1998.. Twenty years, (that includes at least 4 leap days) times 365 days times 16 hours a day... etc means I have had 420,710,400 seconds of time available, and somewhere in there I spent a few of them moving around powercords. I am positive have spent far more time wiping my behind than moving powercords around. But less time doing that than posting around here and other audio sites, since here alone I have managed to whittle away at nearly 6,000 meanderings. You on the other hand, with 95 posts, have certainly been wiping you behind way more than posting... .

Thanks Elizabeth for introducing me to your life. I am very fast at wiping my butt, I built a machine to do that. A jet of water and a washcloth saves a lot ot TP. Water is a more powerfull tool.

I spend most of my time designing and building amplifiers because they are a powerful tool. I make ESL speakers too and drive them directly with 5,000 volt amplifiers that produce 2,500 VA of power. You really can't drive ESLs with much less if you like Miles Davis loud. The Beveridge and Acoustat DD amps were in that range also.  When one is experimenting with ESLs a DIrect Drive amplifier is a very powerful tool as it elimintes the nasty step-up transformer interaction. In the process I found that half the drive power often goes into the transformer at high frequencies due to winding capacitance which is often as large as the capacitance of the paknel.

I quoted you because I am hoping by my little jab that you and others might be interested in learning more about the tools that others are using. You might be interested in my school.http://www.berkeleyhifischool.com/.
Here people can wind their own transformers, build amplifiers of any kind, We keep a few Furtech plugs around for those who like to piddle with such. We also teach people how to put diodes in the plugs to block small DC on the line. Have you tried that?

On the first page there is a link to a talk I gave recently called "Having fun at Burning Amp" where Nelson Pass and I spoke to over 100 hungry audiophiles. What's different about attendees at this annual event is that they want to get deeper into the equipment. Several dozen people took the time and trouble to bring their creations and play them for us in the demo rooms.

The few people there who like powercords make their own. The rest dont really care as there are more interesting things to do like Nelson's amp camp where you actually make an amplifier you can take home and listen to. Wow, what a concept, make a amplifier from a well respected designer like Nelson. He's not waisting his time on power cords.

I have a good freind who buys premium power cords because he likes the way they look. If they make a difference fine, if they dont fine. They are just a pretty thing.

Im on here in the hopes of educating and making suggestions to what people might do to make big improvements in their Hi Fi. I would love to see people direcitly connect ampifiers to the drivers in their speakers, disconnect the crossover, get a line level crossover, choose appropriate amps for each driver. Perhaps some big SS amp for the woofer and some smaller Tube amp for the tweeters. Once you have done that one can turn a knob and have a little more or a lttle less woofer, without having to invoke tone controls. Now we are talking about a big hammer.

Thanks for your response.

Or perhaps a tube amp for everything. Whoa! Did I just say that?! 

Wow, discussions here can get nasty in a hurry...
Roger, I must say you asked for it...

I stuck my neck out but it didn't get cut off yet. I wanted to correspond with people who are really into it and I found one.

Or perhaps a tube amp for everything. Whoa! Did I just say that?!

Of course tubes are great for many applications. When I was a child I built transistor amplifiers, but now as a man I must give up those childish ways. :) 

The first thing that struck me about transistors is how fragile and unforgiving they were and still are. Protecting them is difficult and many protection circuits cause premature clipping into reactive loads like ESLs. 

Tubes need no such protectors. RCA advertised a sweep tube that could take a 400% overload for several seconds. No transistor can do that. 

The output transformer has become a particular curiosity of mine and making them better and better has been a long and exciting journey. I also went down the road of making an OTL with a built in Autoformer. It has many interesting characteristics, one of them being power bandwidth out past 100Khz and very high damping, Futterman style.

I have no fear of high voltage or the quips of those who know little about how amplifiers work. 

I'm just sitting here thinking.....
I'm about 34 miles from the nuclear power plant powering my stereo right now. I've hauled the cable the power company uses. I'm struggling very hard to see how after 34 miles of aluminum and copper cable and buss bar a few extra feet between my wall and my stereo are going to make a big difference. 

I suspect living so close to a nuclear power plant might actually explain quite a few questions I had. 😬

kosst_amojan

I'm struggling very hard to see how after 34 miles of aluminum and copper cable and buss bar a few extra feet between my wall and my stereo are going to make a big difference.

It's a puzzle. Your friendly local audio dealer will probably be willing to loan you a PC so that you can try it for yourself and discover if you can hear a difference. Of course, you may suffer expectation bias because of your "struggling," and that may obscure whatever difference there may be.

Incidentally, the distance between your home and the power plant isn't really important - it's the distance between your home and the substation that really matters. And that's likely to be a lot less than 34 miles.

That’s kind of kosst’s new tagline,

“I’m struggling very hard to see”

What’s the deal with fuses?

What’s the deal with power cords?

What’s the deal with wire direction?

Yup, as expected, another completely pointless comment from geoffkitten. You win for being a consistently useless poster here...Kudos.

I agree 100% that dude is a turkey!!!

et tu brute? 😥

May it be that some of you take a thread like this a little too seriously?

Clearly Geoff is NOT a turkey. Anyone can see he is The Gingerbread Man.                                  
"Run, run, as fast as you can! You can't catch me! I'm the Gingerbread Man!"        

Lizzie can be quite observant. Even my avatar is kind of a Gingerbread Man. 😛