Captive Power Cords versus Swappable IEC Inlets

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miklorsmith

Captive Power Cords versus Swappable IEC Inlets
« on: 7 Nov 2008, 06:32 pm »
I like being able to swap cables but it does feed the nervosa and wallet drain.  What do you think?

Jon L

Re: Captive Power Cords versus Swappable IEC Inlets
« Reply #1 on: 7 Nov 2008, 07:13 pm »
LOL.  Dragging the AVA S**Strom over here, eh?   aa

Personally, I have taken out captive cords and installed IEC inlets on many items, and the result all depends on several factors:

1.  How good/bad the original captive cord was. 

Some captive cords are absolute nightwares sound-wise, but some are actually pretty decent-sounding.  For low-power equipment, a decent 16 AWG captive cord *can* sound fine.  I tend to prefer the unshielded variety in these cases. 

2.  How good/bad the replacement "audiophile" cord is.

Having played around with literally dozens of audiophile and DIY cords, I can confidently say the high price does not say much about sound quality, especially sins of commision. Many audiofool cords tend to *add* colorations, like overly prominent bass, overly edgy texture ("detail"), overly "airy" treble-eccentric sound, etc.  Some decent "stock" cords from Volex and Belden can sound a lot more neutral and less colored by comparison. 

On the other hand, there are some good cords out there that don't necessarily cost $2K but can sound significantly more neutral and less colored while dropping the background noise and resolving more than stock cords.  One has to look hard for these gems...

3.  How sensitive a given equipment is to cord swapping in a given person's electrical environment. 

There are components that change sound to ridiculous degrees with simple cord swaps.  Then there are those that don't seem to respond much at all.  There are also those rare few that seem to sound best with cheap stock-type cords no matter how many cords you try. 

So as usual, YMMV depending on the cycle of the moon.   :duh:

TONEPUB

Re: Captive Power Cords versus Swappable IEC Inlets
« Reply #2 on: 7 Nov 2008, 07:22 pm »
Someone here brought up a very good point about the quality of the IEC inlet.

A few manufacturers have told me that they have had excellent results with the
Furutech IEC inlet sockets and are now incorporating them as standard on their
gear.

Just something to consider.

miklorsmith

Re: Captive Power Cords versus Swappable IEC Inlets
« Reply #3 on: 7 Nov 2008, 07:26 pm »
I wasn't trying to dredge a problem from one place to another but as has been repeated many times here, the manufacturers' circles should be considered safe zones.  This is good in some ways but where there is or could be significant disagreement it stifles one side and prevents a truly unbiased discourse.

fsimms

Re: Captive Power Cords versus Swappable IEC Inlets
« Reply #4 on: 7 Nov 2008, 07:29 pm »
One of the problems with changing out power cords is that the cord is part of a whole system.  Just changing one cord when you have 5 in your system might not allow you to tell much.   If you have a preamp with an internal DAC and only have the amp and CDP player hooked up then you might be able to get a good handle on what the sound of the cord is with your system.   Of course you would have to tie the CDP player to the preamp through an optical cable to isolate the preamp and the amp.

Bob

*Scotty*

Re: Captive Power Cords versus Swappable IEC Inlets
« Reply #5 on: 7 Nov 2008, 07:38 pm »
My biggest problem is with the IEC receptacle itself. It is non-locking and is pathetically easy for a powercord to detach itself from your equipment when you are fumbling around with IC's in your rack.
I would like to see 20amp IEC connections used on equipment and on after market powercords. They might be more resistant to becoming spontaneously unplugged.
 I use after market powercords on my equipment and have variable results like everyone else. I would never spend large amounts money on one however. It's cheaper to find better sounding gear than to throw vast sums of money in the form of powercords at mediocre equipment. A tweak is never a substitute for a fundamentally better sounding piece of gear.
Scotty 

richidoo

Re: Captive Power Cords versus Swappable IEC Inlets
« Reply #6 on: 7 Nov 2008, 08:30 pm »
If the captive cord is only 2 conductors then the component should be double insulated inside to help prevent a shock to the operator. The safety ground is there to trip the circuit breaker in case of a fault.

A captive cord is expected on consumer gear where price and ease of use are a more important factor than sound quality. It is also common to see it on audio gear built before audiophiles learned that power cord quality can affect performance.

The power supply design and parts quality affects the potential benefit of an upgrade power cord. A big transformer and large filter capacity makes a low resistance upgrade cord less important by storing more energy for large signal transients that would otherwise have to come from the much higher impedance wall outlet and high resistance standard cord. Shielding of a single ended PC is less important if a balanced power conditioner is used.

satfrat

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Re: Captive Power Cords versus Swappable IEC Inlets
« Reply #7 on: 7 Nov 2008, 08:55 pm »
I simply look at a captive zipcord as an EMI/RFI antenna and regardless of what type of power conditioning a certain component may have, who needs additional crap coming thru a power cord? Gimmie a shielded power cord anyday at the bare minimum. It's when you start taking the time to compare 6-8 power cords at any given time that things start opening up,,, with the wallet taking the biggest hit. :lol:

I have done IEC conversions to a number of components and I feel every one of them benefited, the latest being my Sony XBR TV. Shielded power cords is the only way to go IMHO,,,, well I should add unless you are willing to hardwire a shielded power cord, which I'm not as if I'm spending $500+ on a power cord, the last thing I want to do is tear it apart so I'll live with an IEC outlet.

Cheers,
Robin

Occam

Re: Captive Power Cords versus Swappable IEC Inlets
« Reply #8 on: 8 Nov 2008, 04:27 am »
One of the problems with changing out power cords is that the cord is part of a whole system.  Just changing one cord when you have 5 in your system might not allow you to tell much.   If you have a preamp with an internal DAC and only have the amp and CDP player hooked up then you might be able to get a good handle on what the sound of the cord is with your system.
I've allways found that the subjective effect of changing one powercord to be readily apparent. Certainly, optimizing all cords is a non trivial task, basically a quasi integer convex linear programming problem with a vague (at best) objective function..... But that is a task we all attempt, maybe not down to the level of powercords (or speaker cables, interconnects...), but certainly at the level of mixing and matching components.

Quote
 Of course you would have to tie the CDP player to the preamp through an optical cable to isolate the preamp and the amp.
I don't understand what you  mean. Would you elaborate?


Regarding captive powercords, its seems to be quite roundabout to put in an IEC. I simply replace the captive cord and plug. But that is because I make my own cords. And 2 prong cords, without a mains ground, allow a very straightforward star-quad construction, with its attendant benefits. Although my experience is relatively limited, 6 different captive cord components, I've yet to encounter any that haven't (IMO) benefitted substantially. I use a 12ga star-quad which is equivalent to 9ga wire, certainly overkill regarding ampacity, especially for a digital source drawing 20watts. For components requiring grounded cords, i.e. non Class II components, I simply hardwire the same cordage and plug(s) that I use in my commercial IEC cords.

I've no issue with captive cords; I've issues with crappy captive cords. By crappy, I don't mean not meeting gauge/current/environmental resistance standards, I simply mean cords that don't 'sound' very good in comparison to others that meet those same standards, or better. 
And yes, IMO, different cordage and plugs subjectively sound different. I've no reason to attempt to prove any of those whatever subjective benefits to anyone, allthough I am attempting to put together a mechanism that might make this possible, for my own uses -
http://www.audiocircle.com/index.php?topic=51928.msg538587#msg53858

For those interested in making their own cables, the Chris VH diy pages are a good read -
http://www.venhaus1.com/diymains.html

FWIW,
Paul


andyr

Re: Captive Power Cords versus Swappable IEC Inlets
« Reply #9 on: 8 Nov 2008, 09:42 am »
I simply look at a captive zipcord as an EMI/RFI antenna and regardless of what type of power conditioning a certain component may have, who needs additional crap coming thru a power cord? Gimmie a shielded power cord anyday at the bare minimum.

Cheers,
Robin

Shirley, if 5' of PC is picking up RFI and that is a good reason to have a shielded PC ... then you are stuffed because the many feet of (unshielded) Romex in your walls has already picked up the same RFI?  :o

If you said you used shielded PCs because you didn't want to "pollute" nearby ICs, I could've understood your reasoning.  :D

And BTW, I'm not sure that a power conditioner takes out RFI?  I thought it just smoothed the voltage?

Regards,

Andy


andyr

Re: Captive Power Cords versus Swappable IEC Inlets
« Reply #10 on: 8 Nov 2008, 09:44 am »

Shielding of a single ended PC is less important if a balanced power conditioner is used.


Hi richidoo,

Can you tell me more about how to implemenmt a balanced power supply?

Thanks,

Andy

Waker

Re: Captive Power Cords versus Swappable IEC Inlets
« Reply #11 on: 8 Nov 2008, 11:11 am »
Amidst all the questions and worries about this or that cord, we are all experiencing similar drawbacks in trying to optimize our audio/visual systems.  As was explained to me, the power company guarantees to supply you with about 220 volts at the service mast on your house.  This voltage is then divided in half in your circuit box for typical 110 volt outlets, or kept whole to run larger appliances in your home.  The problem we all have is that we also share our power with everyone else up and down the street who are on the same pole and transformer, and so what we are all getting is a lot of noise in our power supplies from all the switching on and off of major appliances--refrigerators, washers and dryers, AC and furnace units, etc. There are also fluctuations of voltage with all of that activity.  The result is that the current from any one receptacle in the house is noisy and slightly variable.  Even a dedicated circuit from your own breaker box to your system is subject to all the shared noise and activity on the service line.  (The belief that stereo sounds better late at night is well-founded on the relative decrease in appliance usage up and down the line.)  The solutions are found in isolation products that deliver a clean and rock-solid current to all those fine circuits you have invested in.  And so, which products work well?  Products that offer surge protection by way of fuses stand to limit current to high-demand amps.  I have had great success with a product that actually stores and delivers current on demand while also protecting against power surge.  Check out the site for Richard Gray's Power Company for these items.  Demo something like the 400Pro in your system for a few days, and you probably will not want to return it.  You high-end retailer will gladly oblige you, and it is a simple plug-in-and-enjoy item.  I am running three of these units in one system, and they amount to a component upgrade in lowering the noise floor and revealing more of the music.  Highly recommended through years of careful listening.           

satfrat

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Re: Captive Power Cords versus Swappable IEC Inlets
« Reply #12 on: 9 Nov 2008, 09:11 pm »
I simply look at a captive zipcord as an EMI/RFI antenna and regardless of what type of power conditioning a certain component may have, who needs additional crap coming thru a power cord? Gimmie a shielded power cord anyday at the bare minimum.

Cheers,
Robin

Shirley, if 5' of PC is picking up RFI and that is a good reason to have a shielded PC ... then you are stuffed because the many feet of (unshielded) Romex in your walls has already picked up the same RFI?  :o

If you said you used shielded PCs because you didn't want to "pollute" nearby ICs, I could've understood your reasoning.  :D

And BTW, I'm not sure that a power conditioner takes out RFI?  I thought it just smoothed the voltage?

Regards,

Andy



Who the f* are you calling Shirley? :lol: The name's Robin and I'm a guy. :thumb: To answer some of your concerns regarding Romex caring EMI, I toally agree and that's why I use a BPT (balanced power conditioning) along with other conditioning at the breaker box and along the other circuits within my home. Balanced power does not "smooth out" the voltage. Maybe BPT could offer you a better idea of what their conditioners actually do but my idea is it divides 120v from the positive line to 60v positive/60v neutral and by doing so filters line noise that results in a lower ground noise in your system that allows more music to be heard. After doing all this to reintroduce EMI noise back into an unshielded zipcord is counterproductive imho. Shielded IC's are much better protected than an unshielded PC so I don't undertstand where you're going with that. :dunno: There are many different approaches to power conditioning also. Some infact do just smooth out the voltage but that's just too much of a generalized comment to be making about all power conditioner.

I hope this helps explain somewhat where i'm coming from Andy. :D

Cheers,
Robin

fsimms

Re: Captive Power Cords versus Swappable IEC Inlets
« Reply #13 on: 9 Nov 2008, 09:56 pm »
Quote
Of course you would have to tie the CDP player to the preamp through an optical cable to isolate the preamp and the amp.
I don't understand what you  mean. Would you elaborate?

Cables that go from the CDP player to a preamp have grounds running in the cable unless it is an optical cable.   This ground would cause a ground loop through the power cable grounds and cause RF ringing.   Some power cables are designed to dampen out that ringing.   To dampen out all the ringing, you would need one of those power cables to all but one of the boxes in the system that were connected by interconnects with grounds in the cables.

Bob

mfsoa

Re: Captive Power Cords versus Swappable IEC Inlets
« Reply #14 on: 9 Nov 2008, 10:06 pm »
Quote
Quote from: mfsoa on November 07, 2008, 03:54:33 pm

Since I am a chromatographer, (and can separate and analyze complex mixtures) does this give me any insight into what a certain vodka might taste like? No. Will I tell you that two vodkas taste alike because I cannot measure the difference between them? No. If I measure a difference between two vodkas, will I tell you that you can therefore taste a difference between them? No.



Maybe I am misunderstanding you.  Let's say I have two vodka samples and run a GC-MS with good resolution.  And the two vodka samples have identical peaks.  That is, they contain exactly the same chemicals in the exact same proportions (i.e., you cannot measure the difference).  Let's set aside for a moment that this is doubtless the same vodka from the same batch.  It is not clear to me how these can actually taste different.  Yes, the perception of taste may be different, or the variables affecting taste may be different (e.g., eating a sardine beforehand vs. eating a chocolate).  If you are into perceived benefits, suggest you look at products by Peter Belt (who is at least honest enough to admit that's what he sells) or Machina Dynamica (who is not).

Moving back to wires, I think that it is a reasonable hypothesis that 2 wires manufactuerd by the same company from the same run in the same lengths will "sound" the same.  By "sound" I mean any direct effect of the wire on the sound coming out of the speakers, or any indirect effect the wire may have on active components in the system resulting in an effect on the sound coming out of the speakers.  I am not talking about perceived sound. 

OK?  Identical wires sound identical?  Next, what real material characteristics can change the behaviour of a wire (assuming all external variables are identical).  My short list of main variables are RCL.  There are likely others, such as the much vaunted "skin effect" and crystal structure.  But it is exceedingly difficult to see how these can manifest sufficient change to audibly alter engine performance, except as these variables are manifested as RCL.  Speaker drivers are really best thought of as very simple, inefficient electric engines whose performance is based on EMF.  They don't care about the pain and suffering electrons have passed through in getting to the wires in the driver; all they care about is that the electron moves through the wire and generates an electromagnetic field.  So, there is no reason to believe that there is any characteristic other than RCL with the potential for a change in the sound.  If people feel that there is something else, they should be prepared to demonstrate it; i.e., the burden of proof is on the proponent of a new hypothesis.

So wires with identical RCL should perform identically in an audio system.  Changes in RCL "may" have an audible effect.  (Not power cords, by the way, unless the power supply is poorly designed and/or poorly executed.  An obvious example would be RCL way beyond the bounds of common sense, like a 500 ft 18 guage power cord.)  All of these variables, and their direct effect on signal, can be measured.  Their indirect effect, like high capacitance wires blowing unstable amps is an unknown, but it is probably not unreasonable to assume that minor changes will have negligible effects in well designed well executed equipment.  Note that it is impossible to uniquely assign this effect to a wire, since it is the combination of a wire and specific pieces of equipment.  Note also that such wires seem to be pushing the boundaries of good engineering.

There is little doubt that wires can change the sound of an audio system, though this probably decreases to the extent the componets are properly engineered and manufactured.  The question is whether, within a relatively generous RCL range these changes are audible, and if so, whether the change is "better, "worse" or just plain old "different".  The answers, I think, are "exceedingly unlikely" and "different". 


Zheem,
The only way I'd say those two vodkas taste the same based on measurement is if a few conditions were true:

1) We have reached the pinnacle of analytical chemistry, and are absolutely positive that at no time in the future will we learn anything more about the science behind separation, detection, or even broader, organic chemistry.
2) We also know everything there is to know about the human taste process and how the nervous system and brain figure out what the heck something tastes like, and again are absolutely positive that in the future course of human activity that no new information will be learned about this subject.
3) Now that we know all there is to know about 1) and 2), we must also be absolutely sure that we know everything that will ever be known about the correlation between those measurements and how the mouth/nose/brain system uses the chemical information to produce a certain taste. Again, for the remainder of mankind's stay on this blue ball, we are certain that there will be no advances in this field.
4) We are sure that any molecules not yet constructed will also follow the rules above.

I do not feel that we have reached the above goals, yet folks who say that it is not possible for a powercord to change the sound of a stereo are somehow convinced that no new information will ever be obtained by mankind regarding electricity, circuit design, human perception, the human nervous system, acoustics, electronic measurement etc. Since I see no evidence for this, I must conclude that it is an unsupportable position. Hmmm, interesting that the naysayars position of relying on measurement is rendered meaningless by the very fact that we don't know what the future of measurement will hold!!

My world view encompasses the possibility that maybe someday, something might be learned that wasn't known before. This may be shocking for those who feel that we had electricity all figgered' out a century ago.

And I must wonder why the naysayers are so afraid to just listen. C'mon, it won't hurt!  Why do they have so little faith in their ears, rooms, systems, egos, whatever, that they can't just listen and decide for themselves.

Oh, that's right, they read in a text book somewhere that these equations are well known accurate.

Don't get sand in your ears, guys, if you ever decide to take your head out of it!! :lol:


Thanks for the discussion,

-Mike

andyr

Re: Captive Power Cords versus Swappable IEC Inlets
« Reply #15 on: 9 Nov 2008, 10:25 pm »

Cables that go from the CDP player to a preamp have grounds running in the cable unless it is an optical cable.   This ground would cause a ground loop through the power cable grounds and cause RF ringing.   Some power cables are designed to dampen out that ringing.
Bob


Why would the ground in the (digital) IC going from CDP to a preamp cause a ground loop through the PC grounds?   :?  In my system, anyway, the grounds in ICs connect to RCA barrels which are insulated from the chassis.  PC earths are connected to the chassis ("safety earth") and both PS ground and signal ground are isolated from the chassis.

Regards,

Andy

fsimms

Re: Captive Power Cords versus Swappable IEC Inlets
« Reply #16 on: 10 Nov 2008, 03:22 am »
Quote
Why would the ground in the (digital) IC going from CDP to a preamp cause a ground loop through the PC grounds?     In my system, anyway, the grounds in ICs connect to RCA barrels which are insulated from the chassis.  PC earths are connected to the chassis ("safety earth") and both PS ground and signal ground are isolated from the chassis.

I am sure that on the PC board that at one spot the PC earth is tied to the power supply ground or the signal ground.  They are probably using a "single point ground" system.

From what you say, the RCA barrels go to the signal ground on the circuit board.  This signal ground on the board is probably tied to the to the PS ground which is tied to the chassis and tied to the ground pin of the power cable.  The ground in the power is tied to the power cable of the preamp and that is tied to the ground of the preamp and is tied to the barrel of the preamp's RCA plug.   This goes back to the CDP.    This forms a continous run of copper in a big loop.  That has a resonant frequency in the RF range.   It will ring like a bell.  A properly designed power cord can dappen those vibrations.


Bob

PS I could be wrong but the vast majority of systems are done the way that I posted.

andyr

Re: Captive Power Cords versus Swappable IEC Inlets
« Reply #17 on: 10 Nov 2008, 03:25 am »

... is probably tied to the to the PS ground which, as you say, is tied to the chassis and tied to the ground pin of the power cable.


Hi Bob,

No, I said PS ground is not tied to chassis (and therefore to the IEC ground tag).

Regards,

Andy

JimJ

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Re: Captive Power Cords versus Swappable IEC Inlets
« Reply #18 on: 10 Nov 2008, 05:45 am »
I like being able to swap cables but it does feed the nervosa and wallet drain.  What do you think?

It's less of a hassle if a cable breaks and all I have to do is unplug it instead of taking the cover off and installing a new one from the inside...surplus hospital-grade cables sound just fine to me, so I can't say it causes me to spend any more money :)



whubbard

Re: Captive Power Cords versus Swappable IEC Inlets
« Reply #19 on: 10 Nov 2008, 07:37 am »
mfsoa

I believe that while you may have a point, two Vodkas of the exact same composition should taste the same. Otherwise you are basically saying that two 100Hz sine waves don't sound the same. That two of the same pieces of music don't sound the same. So while measurements can only go so far, I think tha twe have taken them far enough that if two things have the exact same composition, they are the same. Relating to audio, I would say that two cables of the same material and the same contruction are the same.

-West