[DVV]

A lot of double E talk in here - too much for a poor software engineer, power cords are a hardware problem.  This is how I want to address my power cord situation.

1. Purchase a PS Audio Juice Bar
2. Power the Juice Bar with a Shunyata Research Sidewinder
3. Buy Furutech connectors
4. Buy "Bulk" Harmonic Tech single crystal copper wire
5. Build short (1.5 feet) power cords from above components
6. Plug components into Juice Bar using constructed cords.

I can get the Furutech connectors and single crystal copper wire from Bob at audionut.com for around $20 each for the connectors and about $12/ft for the wire.

Whaddya all think of this approach?

What's to think? You have a plan, it sounds like it might work - go for it.

Cheers,
DVV

[nathanm]

Okay, one more question from the non-EE camp; am I correct in assuming that if I were to replace any existing 'weedy' power cables with thick, burly ones, it would be overkill to get anything that was rated beyond what the component draws from the wall, right?  My apt. has 15AMP breakers in the fuse panel, so as long as my power cable can handle 15 amps I should not need anything more, correct?  Hell, my entire combined system couldn't draw more than that or the breaker would blow.  Or are there benefits outside of amperage by having big manly cords?

[audiojerry]

Nathan, do you think it might impress the ladies if you asked them if they wanted to see your big, burly, powercord?

[tmd]

Nathan,
I can't give you a really good technical reason but the bigger the better. One of these days I want to try adding strands to a power cable one by one to see if there is a real point of diminishing returns. Has anyone tried this?
By the way, a 15 amp breaker could have far higher ampreages going through it for very short periods of time constantly and not come close to blowing. (I am talking milliseconds here) They are designed to trip due to sustained overcurrent. Their main job is to protect the cable wired to them so that it doesn't overheat. That won't happen with very short bursts of higher current.
Neil.

[nathanm]

Nathan, do you think it might impress the ladies if you asked them if they wanted to see your big, burly, powercord?

Jerry, if knew what impressed the ladies do you think I'd spend so much time posting to a goddamn audio message board?!  

[dayneger]

When you summarize it so eloquently it's difficult to think of an appropriate response. . .  

[JohnR]

I confess I haven't read this whole thread... it's on my "list" -- things to catch up on

But nathan you're a bit handy, there's a lot of DIY recipes out there. I made some of the "Asylum cords," here's the recipe: http://www.audioasylum.com/audio/cables/messages/7885.html . I can't say what "better" recipes there are or what difference are to commercial products, but these are not very expensive to make and they'll do me for a while.

However I have to say that if you make these the *most* important thing is to get some RED Techflex sleeving from mcmaster.com or maybe partsexpress. That really makes the cables look the part  

[DVV]

Come to think of it, there are just two simple rules:

1. Make your power chord as short as possible, and
2. Use as large a cross section as you can possibly stick into your plugs.

That's it. I tried it and paid like $15-18 (locally) for a heavy duty, quality copper wire, conductors rolled in oiled paper, then insulated by natural rubber, and that much again for really high quality German made plugs (European style).

I compared what I got with a few exotic cables of the same type from Ecosse, Ixos, Kimber and a few others, and I'd never pay the extra 900% of the price for say 2-3% better conductivity.

Cheers,
DVV

[EProvenzano]

Couldn't agree with you more!

[DVV]

http://home.earthlink.net/~rogerr7/wire.htm#longerwires

Just read this, will you?

Cheers,
DVV

[andyr]

No, the shorter is not necessarily the better (... even if it is thick, as the actress said to the bishop!!).

What about the idea that a pwer cord can act as a device for filtering out mains grunge?

If you think this might be true then a 10' (3m) cord is gonna do more filtering than a 5' (1.5m) cord!!

Go visit <www.tnt-adio.com> for their "Carpet Snake" power cord.  This is recommended to be 3m long.

Regards,

Andy

[DVV]

No, the shorter is not necessarily the better (... even if it is thick, as the actress said to the bishop!!).

What about the idea that a pwer cord can act as a device for filtering out mains grunge?

What about it? I never believed it. I do believe a power cord can modify the noise spectrum by virtue of its electrical characteristics, but filter the mains? Not likely. I would love to see some 'scope shots of that, never mind how it sounds.

[quote
If you think this might be true then a 10' (3m) cord is gonna do more filtering than a 5' (1.5m) cord!!

Go visit <www.tnt-adio.com> for their "Carpet Snake" power cord.  This is recommended to be 3m long.

Regards,

Andy[/quote]

I'll look it over, but I fear what I'll see.

Cheers,
DVV

[sac1973]

andyr i liked tnt's diy projects.   there is some stuff that i actually think i can make.

[andyr]

Hi DW,

All I can say is (paraphrasing Julius baby!!) ... I built it, I listened and I heard the difference!

In fact I built 3 different power cords and they all caused different sounds (the testing was done with the power cord plugged into my preamp.  However, I agree that what I was hearing could have been the result of the different cords' basic electrical properties, not their filtering ability.

I have a scope - can you give me instructions as to how to use it to measure main "grunge"?  I have wanted to do this for a while but thought it probably wan't a good idea just to stick the leads in the power socket !!

Regards,

Andy

[DVV]

Hi DW,

All I can say is (paraphrasing Julius baby!!) ... I built it, I listened and I heard the difference!

In fact I built 3 different power cords and they all caused different sounds (the testing was done with the power cord plugged into my preamp.  However, I agree that what I was hearing could have been the result of the different cords' basic electrical properties, not their filtering ability.

I have a scope - can you give me instructions as to how to use it to measure main "grunge"?  I have wanted to do this for a while but thought it probably wan't a good idea just to stick the leads in the power socket !!

Regards,

Andy

Andy, I haven't though about it, but off hand, try measuring frequencies from a signal generator signal passed through the cord. Start from say 1 kHz and work your way up. If your standard input signal, say 1V, starts to decrease by say 20 kHz in any significant amount, say by 3 dB, then you could say it does some filtering. Not much, but it does do it.

Cheers,
DVV

[andyr]

Hi Dejan,

Good suggestion, to use a sig gen into the power cords.

Tonight I have spent a few hours measuring as you suggested.  Alas, I am afraid I did not find any "filtering" whatsoever ... ie. no reduction in signal voltage, up to 100KHz, but I thought people might be interested in what I found.

I'd be interested in anybody's comments upon my musings:

1.  I compared a few measurements between 4 different power cords.  All were about 3m long:
a)  a 'commercial' power cord that you get with a PC - ie., it has a mains plug on one end and an IEC socket on the other.  I call this the 'comm' power cord.
b)  a power cord made from Allan Wright's 'Super Cable Cook Book'.  This used solid-core, 2.5 mm squ. electrician's wire for active, neutral and earth.  The wires were plaited, then I enclosed the result in a copper braid which was earthed at the mains plug.  I call this the 'grey' one (because I used an expandable woven grey sleeve over it).
c)  basically the same as b) but I used a thicker, multi-strand earth conductor.  I call this the 'black' one.
d)  the TNT_AUDIO Snake.  For this, I used RG213 satellite uplink coax for each conductor - active, neutral and earth.  The central core is approx 2mm in diameter (AWG 13) so it is considerably thicker than b) or c).
In addition, the thickness of the insulation around the central conductor obviously separates each conductor, compared to b) and c).  This will affect the cable's capacitance and inductance??

2.  Now the first purpose of my tests was to see whether I could see any 'filtering' of a signal fed into the power cord by the signal generator.

The way I did this was as follows:
*  I connected the sig gen to the active and neutral pins of the mains plug.
*  I connected the CRO to the active and neutral sockets of the IEC plug at the other end.

From 100Hz to 100KHz there was no appreciable difference to the CRO trace ... 2% at max!!

From this, I assume that the power cords were doing absolutely none of the supposed "mains grunge filtering" which I had read that the braided cords should do.

3.  So why would I hear a difference when I compared the result of plugging each cable into my pre-amp?

Maybe because of the difference in R, L & C??

So, as I have an RLC bridge, I decided to measure these parameters for each power cord.

4.  Before I list the results, let me say that from previous listening tests, I had thought the sound of cable d) was the best!  But why should this be??

Because I don't know how to insert a table into this post, I will have to provide a comma-delimited list of results.  I suggest you transpose these onto a sheet of paper to understand the results properly.  The headings of each column are the different cables; the row descriptions are:
* inductance in mH
* resistance in ohms
* capacitance in nF.

a) comm: 0.0031, 0.4, 0.2735.

b) grey: 0.0035, 0.270, 0.2653.

c) black: 0.0038, 0.258, 0.2862.

d) Snake: 0.0129, 0.272, 0.1216.

This shows that:

*  the Snake cable, which uses braided coax, has 4 times the inductance of the others.
Q: why should this be?  Any suggestions?
Q: or is the figure too damn small to worry about anyway?

*  the extra thickness of the RG213 cable doesn't make any difference to the cable's resistance.
Q: why should this be?  Any suggestions?
The higher value for R, for the 'commercial' cable can be expected in terms of a) thin wire used and b) 'enclosed' rather than soldered connectors.
However, I find it surprising that the extra thickness of the RG213 core doesn't deliver any reduction in resistance!
NB: most of the resistance value shown is caused by the connecting wires I had to use, to do the testing!  The slightly smaller result with the 'black' cable is probably due to the fact that this cable did not have an IEC socket on the end ... just bare wires!

*  the Snake cable had significantly lower capacitance than the others - which were all about the same.
Q: does this deliver any benefit?
Q: can anyone explain what the 'Snake' cable has higher inductance and lower capacitance?  Could this be due to the fact that the coax insulation around each conductor separates these conductors from each other?
Q: a slight modification to the 'Snake' cable could be to strip the shield off.  This would leave a cable constructed similarly to b) and c) except that the conductors are separated more, by the insulation ... would this be good or bad!!??

Regards,

Andy

[seppstefano]

Hi Dejan,

Good suggestion, to use a sig gen into the power cords.

Tonight I have spent a few hours measuring as you suggested.  Alas, I am afraid I did not find any "filtering" whatsoever ... ie. no reduction in signal voltage, up to 100KHz, but I thought people might be interested in what I found.

I'd be interested in anybody's comments upon my musings:

1.  I compared a few measurements between 4 different power cords.  All were about 3m long:
a)  a 'commercial' power cord that you get with a PC - ie., it has a mains plug on one end and an IEC socket on the other.  I call this the 'comm' power cord.
b)  a power cord made from Allan Wright's 'Super Cable Cook Book'.  This used solid-core, 2.5 mm squ. electrician's wire for active, neutral and earth.  The wires were plaited, then I enclosed the result in a copper braid which was earthed at the mains plug.  I call this the 'grey' one (because I used an expandable woven grey sleeve over it).
c)  basically the same as b) but I used a thicker, multi-strand earth conductor.  I call this the 'black' one.
d)  the TNT_AUDIO Snake.  For this, I used RG213 satellite uplink coax for each conductor - active, neutral and earth.  The central core is approx 2mm in diameter (AWG 13) so it is considerably thicker than b) or c).
In addition, the thickness of the insulation around the central conductor obviously separates each conductor, compared to b) and c).  This will affect the cable's capacitance and inductance??

2.  Now the first purpose of my tests was to see whether I could see any 'filtering' of a signal fed into the power cord by the signal generator.

The way I did this was as follows:
*  I connected the sig gen to the active and neutral pins of the mains plug.
*  I connected the CRO to the active and neutral sockets of the IEC plug at the other end.

From 100Hz to 100KHz there was no appreciable difference to the CRO trace ... 2% at max!!

From this, I assume that the power cords were doing absolutely none of the supposed "mains grunge filtering" which I had read that the braided cords should do.

3.  So why would I hear a difference when I compared the result of plugging each cable into my pre-amp?

Maybe because of the difference in R, L & C??

So, as I have an RLC bridge, I decided to measure these parameters for each power cord.

4.  Before I list the results, let me say that from previous listening tests, I had thought the sound of cable d) was the best!  But why should this be??

Because I don't know how to insert a table into this post, I will have to provide a comma-delimited list of results.  I suggest you transpose these onto a sheet of paper to understand the results properly.  The headings of each column are the different cables; the row descriptions are:
* inductance in mH
* resistance in ohms
* capacitance in nF.

a) comm: 0.0031, 0.4, 0.2735.

b) grey: 0.0035, 0.270, 0.2653.

c) black: 0.0038, 0.258, 0.2862.

d) Snake: 0.0129, 0.272, 0.1216.

This shows that:

*  the Snake cable, which uses braided coax, has 4 times the inductance of the others.
Q: why should this be?  Any suggestions?
Q: or is the figure too damn small to worry about anyway?

*  the extra thickness of the RG213 cable doesn't make any difference to the cable's resistance.
Q: why should this be?  Any suggestions?
The higher value for R, for the 'commercial' cable can be expected in terms of a) thin wire used and b) 'enclosed' rather than soldered connectors.
However, I find it surprising that the extra thickness of the RG213 core doesn't deliver any reduction in resistance!
NB: most of the resistance value shown is caused by the connecting wires I had to use, to do the testing!  The slightly smaller result with the 'black' cable is probably due to the fact that this cable did not have an IEC socket on the end ... just bare wires!

*  the Snake cable had significantly lower capacitance than the others - which were all about the same.
Q: does this deliver any benefit?
Q: can anyone explain what the 'Snake' cable has higher inductance and lower capacitance?  Could this be due to the fact that the coax insulation around each conductor separates these conductors from each other?
Q: a slight modification to the 'Snake' cable could be to strip the shield off.  This would leave a cable constructed similarly to b) and c) except that the conductors are separated more, by the insulation ... would this be good or bad!!??

Regards,

Andy

Hi Andy, Hi Dejan,
sorry for jumping in between!
IMHO the snake geometry is the main responsible for L, C values.
As the cables are "twisted", they resembles to me right a coil. Just take a section and you see a coil. Of course the resulting L would be greater.

But, with 3 cables, the caps formed by any horizontal section (two cores) "are" in series, so the overall C is the cable section cap, divided by three (it seems a reasonable model, from numbers, doesn't it?).
On the contrary, about R my fancy doesn't help me...

Anyway, recently I upgraded the power cable feeding the CD with a standard shielded thick cable (about 10EUR, to give the idea) and the result was really good. The AMP was not upgraded as it is, guess Dejan, a HK680 (eh, eh).

Ciao, I must beg your pardon as I fear that 99% of this mine is waste of bandwidth but the subject is very interesting!

Stefano

[DVV]

Hi Andy, all,

Let me say it straight out - a job damn well done, Andy! Very thorough indeed.

Hi Dejan,

Good suggestion, to use a sig gen into the power cords.

Tonight I have spent a few hours measuring as you suggested. Alas, I am afraid I did not find any "filtering" whatsoever ... ie. no reduction in signal voltage, up to 100KHz, but I thought people might be interested in what I found.

I should think so! Time somebody put an end to this cable filtering bull - because it is bull. If it filters, then it's because of large capacitance, and I hate to think what that would do the phase of your power sine wave, 50 or 60 Hz, no matter, not to even mention higher up.

I'd be interested in anybody's comments upon my musings:

1. I compared a few measurements between 4 different power cords. All were about 3m long:

a) a 'commercial' power cord that you get with a PC - ie., it has a mains plug on one end and an IEC socket on the other. I call this the 'comm' power cord.

b) a power cord made from Allan Wright's 'Super Cable Cook Book'. This used solid-core, 2.5 mm squ. electrician's wire for active, neutral and earth. The wires were plaited, then I enclosed the result in a copper braid which was earthed at the mains plug. I call this the 'grey' one (because I used an expandable woven grey sleeve over it).

c) basically the same as b) but I used a thicker, multi-strand earth conductor. I call this the 'black' one.

d) the TNT_AUDIO Snake. For this, I used RG213 satellite uplink coax for each conductor - active, neutral and earth. The central core is approx 2mm in diameter (AWG 13) so it is considerably thicker than b) or c).

In addition, the thickness of the insulation around the central conductor obviously separates each conductor, compared to b) and c). This will affect the cable's capacitance and inductance??

As a side comment, you took a good sample. Typical and special, about the same length, exactly the way it should be done.

As for capacitance and inductance I don't know, but I do know it will reduce any crosstalk/crossfeed between them.

2. Now the first purpose of my tests was to see whether I could see any 'filtering' of a signal fed into the power cord by the signal generator.

The way I did this was as follows:

* I connected the sig gen to the active and neutral pins of the mains plug.

* I connected the CRO to the active and neutral sockets of the IEC plug at the other end.

From 100Hz to 100KHz there was no appreciable difference to the CRO trace ... 2% at max!!

From this, I assume that the power cords were doing absolutely none of the supposed "mains grunge filtering" which I had read that the braided cords should do.

Obviously. For your information, a DeZorel LF-A1 Mk.2 filter, their cheapest, will filter by -16 dB at 6 kHz and -38 dB at 20 kHz. For those not familiar with decibels, -38 dB is 79.4:1, or, as opposed to Andy's finding of -2% max, -7,943%, just 3,972 TIMES more. I must add these are measurements I took about a year and a half ago, when I was testing their old series, in the meanwhile they have improved their results. Their current top model, Audio Reference RP1, which I just finished testing, hits -45 dB at 20 kHz, which is 178:1, more than twice that LF-A1 Mk.2.

3. So why would I hear a difference when I compared the result of plugging each cable into my pre-amp?

Maybe because of the difference in R, L & C??

Not so much individually as put together in a complex relationship.

So, as I have an RLC bridge, I decided to measure these parameters for each power cord.

4. Before I list the results, let me say that from previous listening tests, I had thought the sound of cable d) was the best! But why should this be??

Because I don't know how to insert a table into this post, I will have to provide a comma-delimited list of results. I suggest you transpose these onto a sheet of paper to understand the results properly. The headings of each column are the different cables; the row descriptions are:

* inductance in mH
* resistance in ohms
* capacitance in nF.

a) comm: 0.0031, 0.4, 0.2735.

b) grey: 0.0035, 0.270, 0.2653.

c) black: 0.0038, 0.258, 0.2862.

d) Snake: 0.0129, 0.272, 0.1216.

This shows that:

* the Snake cable, which uses braided coax, has 4 times the inductance of the others.
Q: why should this be? Any suggestions?
Q: or is the figure too damn small to worry about anyway?

It is small, but please veiw it in conjunction with the other two. Basically, to put it in plain terms, this cable will influence the voltage to a small extent, but not the current, and since its capacitance is small, it will interact with different power transformers far better than those with higher capacitance.

In other words, any phase shifts will be most likely positive, where voltage will lead over current, while others will tend to go the other way. I would always prefer a positive phase shift to a negative one, personally speaking.

* the extra thickness of the RG213 cable doesn't make any difference to the cable's resistance.
Q: why should this be? Any suggestions?
The higher value for R, for the 'commercial' cable can be expected in terms of a) thin wire used and b) 'enclosed' rather than soldered connectors.
However, I find it surprising that the extra thickness of the RG213 core doesn't deliver any reduction in resistance!
NB: most of the resistance value shown is caused by the connecting wires I had to use, to do the testing! The slightly smaller result with the 'black' cable is probably due to the fact that this cable did not have an IEC socket on the end ... just bare wires!

How about copper purity? Just as I am opposed to snake oil claims regarding materials, so I oppose total denial of the fact that the sheer purity of the material used WILL have an impact. Perhaps small, perhaps down into academic levels, but it will be there. Combine thickness with purity, then throw in some more exotic materials into the mix (e.g. carbon fibre, as done by van den Hul), and you have differences which are very real.

* the Snake cable had significantly lower capacitance than the others - which were all about the same.
Q: does this deliver any benefit?

I believe it does, and for the better.

Q: can anyone explain what the 'Snake' cable has higher inductance and lower capacitance? Could this be due to the fact that the coax insulation around each conductor separates these conductors from each other?

I would think so.

Q: a slight modification to the 'Snake' cable could be to strip the shield off. This would leave a cable constructed similarly to b) and c) except that the conductors are separated more, by the insulation ... would this be good or bad!!??

That's introducing several new variables all in one go. The answer is painfully simple - try it and see, no other way you will ever know for sure.

Now, in view of the figures you provided above, do us all a favor and try again with any one of the cables, but cut down to say one half, or 1.5 m.

These are physical values related to physical properties, so please, don't anybody tell me the length of the cable makes no difference.

Thank you Andy, that was very informative.

Cheers,
DVV

[andyr]

Dejan,

Thanks very much for your reply.  I have one Q which I would be very interested in your comment on.

Let me paste part of my post here:
---------------------------------------
The headings of each column are the different cables; the row descriptions are:

* inductance in mH
* resistance in ohms
* capacitance in nF.

a) comm: 0.0031, 0.4, 0.2735.

b) grey: 0.0035, 0.270, 0.2653.

c) black: 0.0038, 0.258, 0.2862.

d) Snake: 0.0129, 0.272, 0.1216.

This shows that:

* the Snake cable, which uses braided coax, has 4 times the inductance of the others.
Q: why should this be? Any suggestions?
Q: or is the figure too damn small to worry about anyway?
---------------------------------------

Your answer was:

It is small, but please veiw it in conjunction with the other two. Basically, to put it in plain terms, this cable will influence the voltage to a small extent, but not the current, and since its capacitance is small, it will interact with different power transformers far better than those with higher capacitance.

In other words, any phase shifts will be most likely positive, where voltage will lead over current, while others will tend to go the other way. I would always prefer a positive phase shift to a negative one, personally speaking.


Now, your reply was commenting on the "goodness" of cable #4 in terms of its measurements - ie. the TNT-AUDIO Snake cable has low capacitance so that its 4xhigher inductance is not a problem.

Could you provide another reply which comments on cable #2, say.  IE. this cable has 1/4 the inductance of the Snake but more than 2 x the capacitance, so ....

What does this mean in terms of its influence on voltage and current, and its interaction with power transformers?

I will certainly build cable #5, just for fun (ie. the Snake without the shielding), and post my measurements but this will take a while!!

Regards,

Andy

[DVV]

Dejan,

Thanks very much for your reply.  I have one Q which I would be very interested in your comment on.

Let me paste part of my post here:
---------------------------------------
The headings of each column are the different cables; the row descriptions are:

* inductance in mH
* resistance in ohms
* capacitance in nF.

a) comm: 0.0031, 0.4, 0.2735.

b) grey: 0.0035, 0.270, 0.2653.

c) black: 0.0038, 0.258, 0.2862.

d) Snake: 0.0129, 0.272, 0.1216.

This shows that:

* the Snake cable, which uses braided coax, has 4 times the inductance of the others.
Q: why should this be? Any suggestions?
Q: or is the figure too damn small to worry about anyway?
---------------------------------------

Your answer was:

It is small, but please veiw it in conjunction with the other two. Basically, to put it in plain terms, this cable will influence the voltage to a small extent, but not the current, and since its capacitance is small, it will interact with different power transformers far better than those with higher capacitance.

In other words, any phase shifts will be most likely positive, where voltage will lead over current, while others will tend to go the other way. I would always prefer a positive phase shift to a negative one, personally speaking.


Now, your reply was commenting on the "goodness" of cable #4 in terms of its measurements - ie. the TNT-AUDIO Snake cable has low capacitance so that its 4xhigher inductance is not a problem.

Could you provide another reply which comments on cable #2, say.  IE. this cable has 1/4 the inductance of the Snake but more than 2 x the capacitance, so ....

What does this mean in terms of its influence on voltage and current, and its interaction with power transformers?

I wish I could, but that's well neigh impossible, because to be able to do so, I would have to know what the transformer is like. Dan Banquer thinks inductance has little to do with it, in view of the fact that transformers show inductance in henries, not milihenries. I tend to agree with that view.

However, since each and every transformer ever made is also an impedance, the capacitative component could interact in very funny ways hard to predict. Phase shift is definitely on the menu, but to what extent, I cannot know in general.

I will certainly build cable #5, just for fun (ie. the Snake without the shielding), and post my measurements but this will take a while!!

If I was asked to produce a list of what I DIDN'T want in a power cable, it would be like this:

1. Impedance,
2. Capacitance,
3. Inductance, least harmful (within reason, of course).

Let me reiterate - all these are physical values and are in direct connection with the cable's length. If people bend overthemselves to make as short traces on printed circuit boards as they can, surely the cable is no different. Yes, it is bigger and bulkier, but then, it has a much harder job to do.

Cheers,
DVV