Power cords improve audio performance!

[Mr. Skinny]

Darn! I was hoping to make the Power Chord joke!

To be honest, Zircon, I was suprised I got to make it first.

I just figured that if it seemed obvious to me, probably 25 other members were already thinking it.

 

[Mr. Skinny]

I love the guys (and I can't find the link now) that were advocating liquid mercury speaker cables.

Hoo boy.

Highly recommended for homes with pets and small children and other life forms, I'd imagine.

Dang. I'd like to see that link if you find it Fowl.

 

[joe87]

I don't see how a 3-foot power cord could mess up your line voltage, but just any old AC is not necessarily acceptable. If you run your electronic equipment with an emergency generator, you need to make sure the AC produced by the generator is a nice, clean sine wave. Square waves and saw-tooth waves are not good. You need AC with low harmonic distortion. This is something I'm concerned about because I can run my electronic furnace controller and my computer with my emergency generator if the power goes out, and I'm not sure just what the generator puts out. Fortunately, I have backup woodstove heat, so I haven't had to put the generator to the test during winter power outages, but it's nice to be able to check out the weather on the internet during power outages.

From the northern tool catalog, they say their generators have low THD.

Total Harmonic Distortion (THD)
Total Harmonic Distortion is a means to measure the quality of electricity. 6% THD is considered the upper limit for "clean" electricity. Above 6% THD the electricity may reduce the life of electrical circuits, cause microprocessors to malfunction and cause furnace controllers to operate incorrectly. All NorthStar generators have THD less than 6%. Some generators produce THD greater than 15%.

Possibly if a cheap power cord introduces harmonic distortion, it could affect the quality of the sound an amplifier puts out. On the other hand, if you can't hear the difference, why worry about it.

 

[kellyb]

Wow. I work in "live" sound, and we just don't have those kinds of debates in that world.
Probably because we make/service/repair our own cables?

Are these actual engineers that are spreading these weird rumors? Or are they just...people who listen to music or people with Protools on their computer who think they know about sound?
Who are these people?

 

[CaveDave]

Ok, here goes.

I have laughed with the rest of you about the supersaturated WOO that permeates the audiophile world, but there are a few grains of truth hidden inside the sandstorm of misinformation that passes as the current received wisdom in the Audio field.

It all boils down to:

1) E=IR
and
2) P=I^2R

To explain:
E==Voltage in Volts, In this case, voltage drop or loss.
I==Current in Amperes, in this case, the current demanded at the PEAK signal that is instantaneously flowing in the circuit or conductor being considered.
R==The resistance in Ohms of a circuit or segment of conductor, including any thermal or nonlinear effects, at the instant being studied.
P==Power in Watts, in this case, this is lost power.

In a simple case, If there is 120 Volts supplied to your service entry, and the loop resistance is 2 Ohms (1 Ohm out, 1 Ohm return) with a peak draw of 10 Amperes, then there would only be 100 volts at the load due to the 1 Volt lost on each leg of the circuit. And 200 Watts are lost in the loop as heat (wasted).
Now this includes all the small contributions from entry-to-breaker, breaker internal, breaker-to-wiring, wiring-to-outlet, outlet-to-plug, plug-to-cord, cord-to-cap, cap-to-inlet, inlet-to-power supply, and back through to the several connections to the entry, not counting the resistances of each piece of wire in the loop.

Cheap (like come with most equipment) attachment cords are often slim-guage and low conductivity wires with thick insulation and jacketing (To make them LOOK hefty while they are simply cheap).

Can GOOD quality cords help supply better regulated voltage to the equipment? YES.

Do they make up for poor building wiring and devices? NO.

In the case of decent wiring to the outlet, then you may benefit *some* from a better-than-cheap cord, but the entire loop must be good to get the full performance of the equipment.

If your cord or attachments get warm, you are losing power and regulation stiffness.

HTH

Cheers,
Dave

ETA: I meant to expand further, but it is late and I am too lazy to do it now.

 

[a_unique_person]

I just made the mistake of purchasing an audio magazine.

Inside, there is a review of different audio power cords. These just take mains electricity from the socket on the wall the three feet or so to the connector on the back of the amplifier. The prices range from $120 to $220, with the most expensive cord coming out the winner:

I wonder how the audiophiles that believe this bs think the electricity travels for the many miles between the generators and their house wall socket? How do they believe that the super expensive cable that carries the power for the last three feet can make such an enormous difference?

It makes my toes tap! Is there some sort of electric shock emanating from this device?

 

[Ducky]

Highly recommended for homes with pets and small children and other life forms, I'd imagine.

Dang. I'd like to see that link if you find it Fowl.

I'm still searching for it. in the meantime enjoy this craptastic wiki article:

http://www.wikifaq.com/Audio_Speaker_Cable_and_Wire_FAQ


ETA:

FOUND IT!

http://groups-beta.google.com/group...group:*.audio.*&rnum=3&hl=en#0d3e2eff5ce81a4f

Whew. came from this thread started by JJ a while ago:

http://www.internationalskeptics.com/forums/showthread.php?postid=1155995#post1155995

ETA:

You gotta love this quote:

Mercury filled cables suffer from signal-induced magnetostrictive non-linear
microphonics. The resistive impedance has a temporally varying component
with a first derivative w.r.t. time proportional to the second power
of the signal current. This causes multiplicative mixing of the signal
with a signal with all frequencies doubled, causing objective (as
opposed to subjective) sum and difference frequencies. At mechanical
resonance, the electrical signal may cause runaway oscillation resulting
in cavitation, yeilding chaotic resistance phenomena. Near resonance,
high-Q mechanical vibration will cause what laymen call "ringing",
continued oscillation after the driving signal is removed.

Wow. That's some grade-A bulls***.

 

[Wudang]

Reminds me of the New Scientist article about the hifi show where the columnist noted people selling speaker cable for £n,000 per meter. One high-end amp (I think) seller had a problem with his speaker cables so popped out to a nearby hardware store and bought a few metres of their own brand power cable in its distinctive bright orange and paid for with small change. Made excellent speaker cable apparently.

 

[FireGarden]

eric johnson, the man who can identify which type of battery is in his guitar pedals[

(OK, it's from the comments section rather than the interview. But I remember reading an interview with him years ago where he made the claim.)

Again, not an interview but a reference to an interview:

Eric Johnson Profile

In an interview for Guitar Player magazine, he had confirmed he prefers Duracell-brand batteries to power his effects pedals, because they give him better tone. He has also mentioned that, by cleaning his signal path, he has managed to remove the grit from his sound. This actually does make sense and is similar to what many audiophiles do, by using power conditioners and even purchasing battery-powered amplifiers.

It's certainly a wide spread rumour:

Cool Guitar Music

Did U Know? It's said that he can tell you the type of battery used in a pedal just by listening to it - the sound not the battery ;-).

(Smilie inc in original!)


ETA,
In his defence I should say that I have his "Ah Via Musicom" album, and Duracell sound good! (Assuming that's what he used!)

 

[MRC_Hans]

I've spent many hours the last few months discussing the same issues with hifi-freaks on hifi4all.dk (Danish site in danish).

Endnu en dansker. Hej! ... Jeg må hellere kigge lidt på den side .

Mvh Hans

 

[FireGarden]

There's also Duane Allman and nearly flat batteries

Duane Allman

In order to thicken out the sound a little, he used a Fuzz Face distortion box, which he insisted to be used in conjunction with nearly flat 9V batteries. His justification for this was that the sound takes on a slightly creamier quality when the batteries are flat, while the amp can then be used to provide the main raunch and overdrive.

OK,
electronic devices in general working differently as the batteries go flat -- that's reasonable. Maybe different brands have slightly different output? And that could explain Eric Johnson's views?

Mmmm.
Still not convinced.

 

[Mojo]

There's also Duane Allman and nearly flat batteries

OK,
electronic devices in general working differently as the batteries go flat -- that's reasonable.

Especially since what Allman will have been looking for is distortion.

 

[Dog Boots]

Cheap (like come with most equipment) attachment cords are often slim-guage and low conductivity wires with thick insulation and jacketing (To make them LOOK hefty while they are simply cheap).

Can GOOD quality cords help supply better regulated voltage to the equipment? YES.

Do they make up for poor building wiring and devices? NO.

In the case of decent wiring to the outlet, then you may benefit *some* from a better-than-cheap cord, but the entire loop must be good to get the full performance of the equipment.

If your cord or attachments get warm, you are losing power and regulation stiffness.

HTH

Cheers,
Dave

ETA: I meant to expand further, but it is late and I am too lazy to do it now.

I agree with the above - but it's only a matter of wire gauges and such. Cables hand spun by virgins on the backs of unicorns are still BS.

 

[CaveDave]

I agree with the above - but it's only a matter of wire gauges and such. Cables hand spun by virgins on the backs of unicorns are still BS.

Absolutely!
My point was that the power system is a system and can't be tested in isolation from the internal connections and quality of the internal parts (Welds, contacts, etc.).

Cheers,
Dave

 

[articulett]

Same way they believe placing a chip on top of the CD-player improves the sound of the CD.

/Hans

It doesn't?

Well snails sliming across your face still reduce wrinkles don't they? Or has that one been debunked too? I haven't been getting my "what has been debunked" memo--can someone fix this?

 

[articulett]

I agree with the above - but it's only a matter of wire gauges and such. Cables hand spun by virgins on the backs of unicorns are still BS.

Not really--not until consumed and digested by a male ruminant, I think. But it smells the same--maybe worse.

 

[stormer]

I agree, but...

Ok, here goes.

I have laughed with the rest of you about the supersaturated WOO that permeates the audiophile world, but there are a few grains of truth hidden inside the sandstorm of misinformation that passes as the current received wisdom in the Audio field.

It all boils down to:

1) E=IR
and
2) P=I^2R

--snip--

In a simple case, If there is 120 Volts supplied to your service entry, and the loop resistance is 2 Ohms (1 Ohm out, 1 Ohm return) with a peak draw of 10 Amperes, then there would only be 100 volts at the load due to the 1 Volt lost on each leg of the circuit. And 200 Watts are lost in the loop as heat (wasted).

--snip--

I actually agree with you on the calculations, Dave. I just don't agree with the value you choose.

A current draw of 10A needs a cross sectional area of about 1 mm square. If the wire is not the minimum size for the current, the wire will melt, so we can assume the conductor is to spec.

Next, the 2 ohm loop. The resistivity of copper is low that the entire loop has to be about 120m in length. That's a power cord that is 60 m in length.

I think it would have been more fair to use perhaps, 0.034 ohm for a power cord of 1 m length, thus giving 3.4 W power loss in the power cord. (Although if the power cord was really 2 ohm at 60 m long, your calculations would be valid)

 

[CaveDave]

I actually agree with you on the calculations, Dave. I just don't agree with the value you choose.

A current draw of 10A needs a cross sectional area of about 1 mm square. If the wire is not the minimum size for the current, the wire will melt, so we can assume the conductor is to spec.

Next, the 2 ohm loop. The resistivity of copper is low that the entire loop has to be about 120m in length. That's a power cord that is 60 m in length.

I think it would have been more fair to use perhaps, 0.034 ohm for a power cord of 1 m length, thus giving 3.4 W power loss in the power cord. (Although if the power cord was really 2 ohm at 60 m long, your calculations would be valid)

I was counting the entire loop from the service entry (the utility meter) to the load, including all connectors and wiring devices and the building wire. But I did just pull a number (1 ohm each way) out of my @$$ for ease of cacculation, to show how important small losses can be.

I have seen cheapo extension cords where not only was the wire the minimum size to carry the rated load, but the alloy was low grade and the contacts were cheap and poorly bonded to the wire. Near maximum load the ends would get quite warm.

Cheers,
Dave

ETA: I also intended (but got lazy) to illustrate the fact that as the load changes with the music, the losses change and the voltage at the load will vary, possibly affecting the sound quality.

 

[stormer]

You can't change the entire loop....

I was counting the entire loop from the service entry (the utility meter) to the load, including all connectors and wiring devices and the building wire. But I did just pull a number (1 ohm each way) out of my @$$ for ease of cacculation, to show how important small losses can be.

--snip--

ETA: I also intended (but got lazy) to illustrate the fact that as the load changes with the music, the losses change and the voltage at the load will vary, possibly affecting the sound quality.

Once again, I agree with you on the whole, Dave.

The entire loop from the watt-hour meter through the wall wiring through the power socket through the power cord into the transformer in the equipment and back again may easily be more than 2 ohms. But we are talking about "magic power cords" here though, and how much these cords will affect the audio.

I agree that if you use less than minimum spec wiring, going to proper spec will help. Nothing much you can do about the entire electrical loop, so let's look at only the power cord.

How much effect does a properly specced and constructed power cord affect the audio as compared with them "magic power cords"?


And for your "ETA", equipment is run from a d/c supply internally with the support of large value capacitors to provide a stable voltage. A properly designed regulated power supply will provide a stable d/c that should not be affected by the load. Even if they were not properly designed psus, how will the "magic power cord" affect the d/c voltage?

 

[todd]

a "real" difference

isn't it possible that there is a measureable mechanincal/electronic difference in current that doesn't amount to a measurable audible difference?