cleeds Is it because of the better quality AC connectors? Is it the geometry of the cables themselves? I honestly don’t know. And I don’t care. And this being a hobbyist’s group, Add, it is possible the cord used is helping to prevent induced AC voltage and noise from transferring onto nearby ICs. I’m not required to satisfy anyone’s demands for technical proof of any kind. Add me to that camp! I really don’t care why it does what it does. There are plenty of credible theories out there to read for those that want the why. I am currently running early 1960s Amperex 6922 PQ white label tubes in my Sonic Frontiers preamp. To my ears I prefer how my audio system sounds with the tubes over current production Sovtek or EH 6922 tubes. Measurements? On my Hickok 6000a tube tester they measure the same. Measure the same??? Then they have to sound the same. Measurements don’t lie. Right?! Jim |
djones51544 posts12-17-2018 1:13pm
I guess I don’t understand what a power cord does. I though it basically extends the romex in your walls from the panel box to your component, whether it’s an amp or vacuum cleaner. So if the romex is good enough from the panel box to the receptacle why isn’t the heavy guage wire the amp company supplied with their amp good enough, as long as it meets specs for what it is designed for or should you change out the romex in the walls for the same wire as your mega $$$$ 6 feet of cord? It’s not as if it’s doing anything other than supplying electricity to the component. We could also extrapolate this back through the power grid to the generating plant. I though it basically extends the romex in your walls from the panel box to your component, whether it’s an amp or vacuum cleaner. No..... The power cord is an extension of the leads of the primary winding of the power transformer of the equipment. It’s not as if it’s doing anything other than supplying electricity to the component. But yet it does....... We could also extrapolate this back through the power grid to the generating plant. No..... Technically only back to the step down utility company’s isolation power transformer that feeds your house and any other houses that may be connected to the isolation transformer. |
If you don’t think power cables matter at all, please refrain from derailing the conversation with antagonism. There a time and place for that but not in this thread please.
mkgus12-16-2018 11:06am @mkgus That didn’t happen did it?.... Over 90% of those that posted to your thread are naysayers. And the majority of them are from N/A countries. N/A?? Hell, they must be ashamed of where they live. You should put this thread out of its’ misery and delete it. Yes you have the power! Just click on the thingy that looks like a sprocket inside a square to the right hand side of the header of this thread. Enter delete. |
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nonoise4,189 posts12-19-2018 11:36am
The reason I never replied to @prof was that I went to sleep after my last post. The urgent and provocative nature of his reply belies what seems to be a basic need to argue, however skillfully, to no apparent end. The man loves to hear himself talk.
Waking up to the provocations and like was entertaining, to say the (really) least.
His analogies are tangential at best, as they are off the subject and designed to lull lessor discerning folk into conflating an obvious conclusion with one not really relatable. Nice tactic.
It’s like listening to a broken record. Take placebo. This has been hashed to death and yet it rears it’s stupid head. When it comes to audio, anyone can be fooled by a cheap parlor trick, as it’s done in the short term. Myriad variables are introduced in a A/B test that are simply not present when listening as a pleasure.
After being fooled in a A/B test, one simply goes back to their system and in short order, they can recognize the differences that fooled them after immersing themselves in a listening session. The placebo excuse assumes that we all go on listening the wrong way. A simply silly notion.
To assume that we are so fallible, broken and easily fooled all day, every day, and we are not to trust our senses, begs the notion as to why we’re all still alive, having not blown up, shocked, or killed ourselves in some silly manner due to placebo, or some other phenomenon.
All the best,
Nonoise And that is the reason many members no longer post on threads like this one anymore. They are tired of hearing the same naysayers BS. The OP last sentence of his posted message. If you don’t think power cables matter at all, please refrain from derailing the conversation with antagonism. There a time and place for that but not in this thread please. The OP was clear he could hear differences. He was just asking why? He wasn’t asking for an intervention to change his mind.... Do any of you non believers think you have changed the minds of the believers? Have you changed the mind of the OP? I wish Agon would adopt a mission statement similar to that of the Cable Asylum. The Cable Asylum is for those who have decided that audio cables make a sonic difference. If you do not feel that audio cables do sound different, then do not post here. Posts that state that audio cables sound the same, or that all one needs is zip cord and/or dimestore coax, may be deleted, re-directed or other actions taken at the sole discretion of the moderators or the Bored. If you post more than one such post, you may be banned from the Cable Asylum. For you non believes start your own thread about cables in another Agon forum. Heck, maybe Agon could give you a forum with a mission state for non believers only. If you believe cables can sound different post elsewhere on an Agon forum. Example, The Cable Forum. . |
markalarsen345 posts12-19-2018 11:56am
Power cables are all about EMI. Not entirely. There are other factors that go into the making of power cables. The type of male and female connectors used. Type of metal used. Plating? Type of plating used. How well the female IEC connectors grips the male inlet connector of the equipment. Wire gauge size. Stranded wire or solid core conductors. Type of Insulation dialectic material used. The geometry of how the cable is made. How is the equipment grounding conductor incorporated in the design of the cable? The type and method of the shielding used in the cable. |
geoffkait13,241 posts12-19-2018 4:25pm
mkgus
13. Cable constructions of multiple gauge wires that influence the way high, medium and low frequencies propagate through the power cable.
>>>>Whoa! What? I did not know there were high, medium and low frequencies traveling through the power cord. I was under the impression it was current and voltage, alternating at 60 Hz. 😳 >>>>Whoa! What? I did not know there were high, medium and low frequencies traveling through the power cord. I was under the impression it was current and voltage, alternating at 60 Hz. 😳 @ geoffkait 60Hz, yeah, if all you have connected to the AC power mains in your home are incandescent light bulbs. Any electronics in your home? Audio system? TVs? Computer/s? Appliances with a micro processor? How about CFL and LED lights? Any fixtures with electronic ballasts? Gas furnace with a blower fan controlled by a VFD? Here in the USA our homes are stuffed full of equipment and appliances that are spewing harmonics back out onto the AC mains. Maybe a lot of it from our audio equipment. https://www.electronics-tutorials.ws/accircuits/harmonics.html |
Measurements? If we can hear it then it can be measured. Can it? John Curl Interview Page 15/18 I was working with Noel Lee and a company called Symmetry. We designed this crossover and I specified these one microfarad Mylar caps. Noel kept saying he could ’hear the caps’ and I thought he was crazy. Its performance was better than aluminum or tantalum electrolytics, and I couldn’t measure anything wrong with my Sound Technology distortion analyzer. So what was I to complain about? Finally I stopped measuring and started listening, and I realized that the capacitor did have a fundamental flaw. This is were the ear has it all over test equipment. The test equipment is almost always brought on
to actually measure problems the ear hears. So we’re always working in reverse. If we do hear something and we can’t measure it then we try to find ways to measure what we hear. In the end we invariably find a measurement that matches what the ear hears and it becomes very obvious to everybody. http://www.parasound.com/pdfs/JCinterview.pdf. |
jeffwyo577 posts12-21-2018 9:20amI guess you need to tear out all the drywall & change all the 12 or 14 ga romex that is is your house too then, make sure you use gold plated outlets. @ jeffwyo57 Actually 2 conductor with ground NM sheathed cable (Romex is a Trade Name for NM sheathed cable) is quite good for branch circuit wiring. The design make-up of the cable helps cancel any induced voltage on the equipment grounding conductor. Better though, is aluminum armor 2 wire with ground MC cable. Worse is metallic conduit with the Hot, neutral, and insulated equipment grounding conductor pulled randomly in the conduit.
Actually testing measurements? Oh yes, for you nay-stayers.
Read pages 31 through page 38. https://centralindianaaes.files.wordpress.com/2012/09/indy-aes-2012-seminar-w-notes-v1-0.pdfI live in the USA. May I ask what country you live in? Jim |
elizabeth6,035 posts12-22-2018 12:30pm
How long can these threads be dragged out?
And how many repeated posts, notions, arguments, rants, cries for help... will it take before we all just get tired??? LOL elizabeth If we can convert just one naysayer to a believer it is worth it. Even on this thread there has been members that have said they finally forced themselves to listen to an aftermarket cable and confessed, yes, they could hear a difference. There’s hope...... |
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@ prof Other than a price target what determined, determines, the equipment you bought, buy, for your audio system. 1) Brand manufacturer name? 2) Equipment features? 3) Dealer recommendation? 4) Manufacture’s specs? Surely not! They can’t be trusted. 5) Audio magazine review? NOT! They definitely can’t be trusted. 6) A flip of a coin? 7) How it sounded to your ears? You liked how it sounded to your ears....... ......... |
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A member on SH forum posted this response. Any validity to his theory? oxenholme said: ↑ Is an even lower noise floor likely to result if in addition one has a dedicated ring main wired with the same cable as used in the wonder power cord? No doubt even better if the entire run to the electricity substation could be rewired similarly? Happen UK mains sockets and plugs will work better too due to the larger contact area. Should one have the contacts therein 24 carat gold plated to improve the connection? Another thing to consider about the UK and Europe is the higher AC mains voltage. Here the step-down ratio of the power transformer in a given audio component will be twice the ratio of the same component in the USA.
This means that mains-borne noise that is inductively coupled across the transformer windings will be attenuated by 6dB more in the UK than the USA. (This depends on the frequency response of the power circuit and the type of transients and noise coming from the mains however.)
I wonder whether the sceptics on these threads tend to reside in higher voltage territories, and the supporters in low voltage republics? Grower of Mushrooms, Yesterday at 2:02 PM #58
I wonder whether the sceptics on these threads tend to reside in higher
voltage territories, and the supporters in low voltage republics?
I have wondered this too. It seems the majority of the naysayers on this Agon thread list their country as N/A. |
pkvintage39 posts12-24-2018 10:52am
What happens when you plug an expensuve power chord into a cheap power bar that is plugged into a $1.00 wall socket? Or is it automatically assumed that a power conditioner is part of the equation. If not where should the quality power pieces begin? You may/will still hear a difference from your system. If the power cord is designed to be connected to a piece of digital equipment like a CDP, Dac, or CD transport the chances are greater of hearing the difference, jmho. As for improving the parts of the AC power delivery system it’s all cumulative. The branch circuit wiring, there in, a dedicated branch circuit. The type of wiring used and the wiring method used in installing the branch circuit wiring. Quality of wall receptacle used. You don’t need to spend big bucks on an audio grade outlet to hear an improvement over a cheap residential grade outlet. Even the receptacle cover plate can make a difference. . |
erik,
Please explain how the noise of the switching of a full wave rectifier in a power supply can pass back through the primary winding of the power transformer and through the power cord and end up on the AC mains.
Jim |
erik,
I am not disputing anything you said in your previous post. I am in agreement with most of what you said.
My understanding is the noise created by the rectifier does indeed end up on the AC mains unless the designer/manufacturer of the equipment adds some type of filter on the AC line of the equipment. My understanding, from what I have read, digital equipment is the worst.
So if noise on the AC line can cause distortion in audio equipment, then it stands to reason, if, say a CDP is putting noise back out on the AC line, the noise will inter through the power cord of a preamp that is plugged into the same wall mains AC outlet as the CDP. Correct?
Jim
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@ elizabeth About 15 years ago I built a power distribution center using a non ferrous aluminum alloy 2 gang Bell Box. https://www.homedepot.com/p/BELL-2-Gang-Weatherproof-Box-with-Five-1-2-in-Outlets-5334-0/203638230?M...Power cord is an Audioquest AC 12 I had. I used a non ferrous type cord strain relief connector to connect the cord to the Bell box. The two duplex receptacle outlets are the original manufactured Hubbell HBL8300H hospital grade outlets. (I got them for free.) Duplex cover plate is a Cooper Industries non ferrous 2 gang stainless steel cover plate. Jim |
@
fleschler
Roger basically takes the attitude that if a PC makes an amplifier sound different, the amplifier has an inadequate power supply or design. Only his RM line of amps are correctly designed and built because they are are unaffected by different PCs. I take him at his word, for his designed equipment.... Can he speak for all designers of audio equipment? NO! It should be said if you design it that doesn’t mean the manufacture will build it. I remember reading an article where John Curl said he would spec a certain grade of components, for a piece of Parasound audio equipment he designed, only to be overruled the owners of the company saying it would make the price of the piece of equipment to high and price it out of the market competition. |
erik
If you visit the Cable Asylum forum you can read where many members build their own DIY power cords. You don't have to spend a fortune for a good power cord.
Jim
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spatialking145 posts12-24-2018 3:10pm Please explain how the noise of the switching of a full wave rectifier in a power supply can pass back through the primary winding of the power transformer and through the power cord and end up on the AC mains. I can answer this question - what happens is the spike is transmitted both via radiation and by conduction through the transformer. Power transformers do have a bandwidth and it is surprisingly wide. I don’t believe I have ever measured a line isolation transformer with less than 100KHz of bandwidth, although they are not always flat.
So, the diode switching on and off creates a current surge when it turns on and another when it turns off. Given we have inductance in the transformer as well as the line itself, the current starting and stopping abruptly causes a spike in noise on the line. That spike is sent out through the power cord and will affect anything susceptible nearby on that line. Some amplifiers designs have components to squash that spike internally when it is created, others do not.
The voltage spike is dependent upon the change in current divided by the change in time times the inductance. That is, the bigger change in current when the diodes turn on or off creates a bigger spike. The change in time is dependent on the turn on or turn off time of the diode, determined internally by the design of the diode. The inductance is both the transformer and grid together.
erik_squires is right, one does not want that noise coupling into audio equipment. If one has a transparent power cord connected then that equipment has to deal with the noise. If one has a power cord connected that doesn’t conduct the noise, then the equipment doesn’t have to deal with it. Sooo you have measured it. Not theory but fact. It’s measurable. Now for the million dollar question.... Will a well designed power cord stop the noise from reaching the AC Line mains receptacle outlet? |
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bigkidz1,711 posts12-24-2018 8:03pm
Assuming this is all true, so now my question is why do some of these cords/cables cost so much? Materials are not "that" expensive (copper wire for a six foot cable, silver wire, shielding, etc.)
You can always save a few bucks and build your own. You can buy the cable by the foot. Buy the connectors for the ends of your choice. Just scroll down the page to AC power cable. https://www.vhaudio.com/wire.htmlHome page .
https://www.vhaudio.com/There are other sites you can buy from as well. . |
@ geoffkait , Web Link for the audioquest white paper you posted, please. |
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mkgus OP28 posts01-03-2019 8:44pm I don’t think power cables should be as mysterious as they are. There are a lot of good suggestions in this thread, but I have yet to see a published scientific study covering any of these ideas in depth. I agree with nonoise that it’s a possibility we just don’t yet know how or what to measure to understand certain complex phenomena in the world of audio reproduction. Don’t worry about that, I’m too far down the rabbit hole. Save yourself! After hearing the change in sound when I swapped from stranded core to solid core speaker cables, my curiosity was peaked. After that was experiencing differences in RCA cables. @ mkgus Please produce any published credible 3rd party testing results that show why, how, speaker cables and interconnects have an impact on the sound of an audio system. You can’t..... It’s just theory. No measurements, just theory. But you know they make a difference from listening to them and have accepted that they do make a difference. But you really don’t know why. So why are you hung up on why power cords make a difference? You yourself said you can hear differences. You have yet, unless I misses the post, described the differences you hear when using an aftermarket power cord compared to a stock OEM power cord. Please explain the differences you hear. . |
colin44ct35783 posts01-13-2019 4:26amCAPS, the bigger the better, pump the current...limit voltage drops and drive the spl.Most transformers, the most expensive and important part have become so small over the years...but monster caps refreshed at 50-60 times per second does the job...if they can melt or brown a bus bar its all good! @ colin44ct357 Sounds pretty simple doesn’t it? This guy is a designer and a manufacturer of audio equipment. I have to admit, the first time I heard how much difference a power cord could make, it really bothered me. It wasn’t like it was subtle.
But its not hard to measure the effects of a power cord and with minimal equipment, you can sort out what’s going on. I’ve already done that. So:
There are two aspects, AC voltage drop and high frequency current limiting.
AC voltage drop is the voltage dropped from the wall to the input of the equipment in use. I’ve measured a loss of 40 watts on an amp that makes 140 watts, so no-one should be surprised that that might be audible as well. I used a 3 1/2 digit DVM to measure the voltage drop and it showed around 3 volts. This was a pretty standard but inexpensive Belden cord. A more expensive Belden cord with heavier gauge showed a lessor drop and more power out of the amp. So no mystery here.
The second issue is the high frequency current limiting. This is a bit trickier to understand, but its not quite rocket science. Almost any power supply consists of a power transformer, rectifiers and filter capacitors. When the the transformer voltage is higher than the capacitor voltage, the rectifier commutates (a fancy word for turns on and conducts). At that point the filter capacitors can charge up and will do so until the power transformer voltage falls low enough that the rectifiers cut off.
At that point the circuit using the power supply drains the filter caps. Since this happens 60 times a second, the drain is usually not very much at all, so its only at the very peaks of the AC waveform that the caps are be replenished. There might be only a few microseconds or milliseconds that this can happen, and quite a bit of current might have to flow during that time, essentially a high frequency event.
If the power cord limits current during this period, the performance of the circuit using the power supply might suffer, possibly due to increased IMD since the DC might have a bit more of a sawtooth on it than if the current was not limited.
There are some take-aways; if the circuit is heavily regulated, the power cord will make less difference. If the connections at either end of the cord gets warm during operation, you can count on a voltage drop. How much the voltage drop in a power cord affects the audio performance depends on the AC wall voltage and the equipment itself.
A lot of people point out that there is wiring in the walls and from the power company and so on. Of course! But Romex is pretty high performance; if you could legally sell power cords made of Romex they would have excellent performance. But that would pose a fire and shock hazard so power cords are all about how to work with stranded wire.
One way to measure a power cord’s performance is to measure the effect it has on the equipment in use. This is how I discovered that 40 watt loss I mentioned. If you have enough time and toys, you can set up a microphone in the room and measure frequency response and distortion rather than just testing the gear on the bench. I have a customer that used this technique to test filter capacitors in the power supplies of his amps.
This guy is also a designer and manufacturer of audio equipment. Power Supplies: Commentary for Consumers by Nelson Pass | Aug 1st 2009
In an amplifier, your utility, house wiring, power cord, and transformer provide the rain. The capacitor bank is the reservoir. The capacitors receive electrical charge every 1/120th of a second, reflecting two pulses of current from the transformer for every cycle of the 60 Hz sine wave provided by the power company. These pulses are of relatively short duration, and it is up to the power supply capacitors to store energy during the 6 millisecond or so electrical drought that occurs between charge pulses. We want a constant voltage (water level) from our power supply, and this is usually achieved by the use of large capacitors which store more charge, and large transformers which provide as much charge as is needed. You get the idea. Since we are not designing amplifiers here, but rather trying to get a handle on what constitutes quality in a market full of hype, I want to talk about some general ideas and comment on some of the common approaches used by manufacturers. Understand that we simply want a constant, noise-free, voltage to be available from a power supply, regardless of how much demand we place on it. https://www.passlabs.com/press/power-supplies-commentary-consumersHere is a post by an guy with a B.Sc.E.E degree. Note the date of the post, 2001. Science and Power cords 194.255.242.135
Posted by Ole Lund Christensen on April 21, 2001 at 16:49:18 In Reply to: Dissenting OPINION posted by waVeman on April 20, 2001 at 14:29:44: Some years ago a dealer wanted to show me the major improvement in sound caused by using a new power cord.
I was politely saying no, do not waste my time. But he insÃsted, and as he was an importantant dealer for my products, well I accepted to listen to a track on a CD, and then letting him change the power cord, and listen to the same track again.Having a B.Sc.E.E degree I knew that nothing would happen, and he was just victim of the placebo effect and a "snakeoil" cable distributor. So my brain was trying hard to ignore the message from my ears, I was hearing a major improvemnt of the sound. But as the truth is more important to me than my pride, I had to admit to the dealer, that I heard this improvement he was raving madly about. I left the shop, and spent 6 months trying to figure out what was going on. When the power has traveled 20.000 meter through standard cheap cables and connectors and fuses from the power plant to the shop, why did the last 1 meter cable matter? One day it hit me hard, it does not make sense because I am asking the wrong question.
the right question is: Why does the first 1 meter matter?
And the answer comes easy: Because the source of the problem is inside the power amplifier, it is not 20.000 meter away.
The power amplifier generates a lot of noise from the rectifier, and
the current in the power cord is very distorted. So the power cord is an antenna, radiating noise to all other components and interconnects.
So a shielded power cord reduce the radiation, and different connectors and cable designs affect the high frequency signals. Today all this is standard stuff, which you are required by law to measure to get EMC/CE approval in Europe, and there is lots of laboratories that measure this every day. So I have learned to listen and consider carefully the next strange idea. https://www.audioasylum.com/audio/general/messages/11/117899.html. |
mzkmxcv334 posts01-13-2019 8:49am@elizabeth
If
I can easily show that the sound coming out of your speakers is still
the same regardless of “upgrading” power cords, what argument would the
“believers” have then?
What a bunch of BS! What test equipment do you use to measure for Fullness and Timbre? |
mzkmxcv336 posts01-13-2019 9:04am@jea48
“Fullness” is a meaningless term, so not sure (do you mean deep bass?). Timbre is harmonics, so that’s easy.
However,
no solid state amp should have timbre anyway, it should only output
what the input signal dictates. However all amps have some THD/IMD, but
when it’s 80dB down, it’s not important.
Again, BS.
timbre
noun
tim·bre
| \ˈtam-bər,
ˈtim-;ˈtam(brᵊ)\
variants:
or less commonly timber
Definition of timbre
: the quality given to a sound by its overtones: such as
a
: the resonance by which the ear recognizes and identifies a voiced speech sound
b
: the quality of tone distinctive of a particular singing voice or musical instrument
Fullness? As in the sound Jennifer Warnes voice singing "Famous Blue Raincoat". Or the sound of the piano when listening to any of Diana Krall CDs. Just curious what is your opinion on interconnects and speaker cables? Do they make a difference in what we hear? . |
mzkmxcv337 posts01-13-2019 10:42am
@elizabeth
the treble has more clarity. easier to understand female vocals, hear cymbals clearly, massed violins sound as a group of separate instruments, not just some clump of noise
@jea48
Are you unaware that overtones are harmonics?
As for interconnects, as long as they are well enough shielded, then yes (at least in regards to audible changes). @mzkmxcv Harmonics? Yeah, I am aware of Harmonics. Can they pass through the windings of a power transformer of a piece of audio equipment? Can they be radiated? How far? As for interconnects, as long as they are well enough shielded, then yes (at least in regards to audible changes). Any proof? Actual test equipment measurements performed by credible 3rd party testing lab. Please produce a credible Link to a white paper showing ICs make a difference, why and how. Not theory, actual measurements. . |
mzkmxcv339 posts01-13-2019 11:30am@jea48
I don’t have a subscription to access AES papers, so nothing 100% credible, but here are some measurements of RCA cables. Of course it’s not Nordost Odin 2 or anything that ridicoulous. As for the stereo crosstalk, keep in mind even the worse offender is still well below the signal to be considered inaudible, and the 3” generic cable performed similarly/better than the 3” “expensive” silver one.
EDIT: Wonderful, just notified some of my comments were removed, even though they break none of the guidelines. Love the open discussion. @ mzkmxcv, Sorry, Not what I would call reliable credible proof. Who is the guy? What is his back ground? You’ll have to better than that. His bench setup could have caused his measurements to be flawed. Wouldn’t be the first time. EDIT: Wonderful, just notified some of my comments were removed, even though they break none of the guidelines. Love the open discussion. Notified by Agon through an email? Was the material copyright protected? From my experience here on Agon they do not edit a post. They just remove the entire post. OR EDIT: Wonderful, just notified some of my comments were removed, even though they break none of the guidelines. Love the open discussion. "Wonderful, just notified some of my comments were removed,". Did you mean to say "noticed" instead of "notified"? If you meant to say noticed it could be you did not proof read the page before posting it to make sure everything you typed was there on the page. Maybe it’s just my computer but only on Agon if what I am typing goes beyond the bottom line of the message box it is not being saved. If you find yourself at the bottom of the page, add more space by hitting the enter key several times. . |
@ mzkmxcv jea482,855 posts01-13-2019 10:54am
mzkmxcv337 posts01-13-2019 10:42am
@jea48
Are you unaware that overtones are harmonics?
As for interconnects, as long as they are well enough shielded, then yes (at least in regards to audible changes).
@mzkmxcv
Harmonics? Yeah, I am aware of Harmonics. Can they pass through the windings of a power transformer of a piece of audio equipment? Can they be radiated? How far?
Again, Can they pass through the windings of a power transformer of a piece of audio equipment? Can they be radiated? How far? Specifically the harmonics created by, A light dimmer. Harmonics created by a switch mode power supply? Harmonics created by a full wave bridge rectifier found in the power supply of audio equipment? . |
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mzkmxcv346 posts01-14-2019 6:19am
Thanks for the response. Timbre Timbre is harmonics (overtones), this is easily seen by inputting a signal and seeing what the FFT/distortion graph looks like. I personally believe that no gear should have timbre, it should only be transparent and accurately reproduce the timbre of the instruments in the recording. Of course most speakers have timbre, but any expensive solid-state amp, DAC, or preamp that is competent will not have audible distortion/timbre.
@mzkmxcv Definition of Timbre. tim·bre | ˈtam-bər, ˈtim-;ˈtam(brᵊ) variants: or less commonly timber Definition of timbre : the quality given to a sound by its overtones: such as a : the resonance by which the ear recognizes and identifies a voiced speech sound b : the quality of tone distinctive of a particular singing voice or musical instrument https://www.merriam-webster.com/dictionary/timbre noun- Acoustics , Phonetics . the characteristic quality of a sound, independent of pitch and loudness, from which its source or manner of production can be inferred. Timbre depends on the relative strengths of the components of different frequencies, which are determined by resonance.
- Music . the characteristic quality of sound produced by a particular instrument or voice; tone color.
https://www.dictionary.com/browse/timbreQuality of a sound. Can one manufacturer’s microphone reproduce the sound of Jennifer Warnes singing into it differently than another manufacturer’s microphone? What test equipment is used to determine which microphone more accurately reproduces Warnes’ voice? What baseline is used for the test equipment? In other words, what piece of test equipment was used first to capture the quality, Timbre, of Warnes’ voice as she was singing into the two microphones? Would you agree with this video? https://www.youtube.com/watch?v=144QVYv__S4
Though here is a manufacturer’s video, would you disagree with what is said on the video? https://www.youtube.com/watch?v=BLoM9bBr8lc. |
mzkmxcv348 posts01-14-2019 9:59am@jea48
Any decent amp/DAC/pre will not allow any distortion from your other appliances to affect your gear, unless talking ground loops.
Stereophile (among other resources of course) has measured hundreds/thousands of pieces of equipment other than speakers, and most all preform to spec, and JA isn’t using any $5000 power cords, and he lives in a NY apartment/housing complex if I’m not mistaken. Are you saying you can get better than advertised specs if you upgrade the power cords?
PS Audio sells “high end” power cords, and even he basically said, in his rebuttal to null tests, that their only real benefit is better shielding for EMI, if you look at the measurements of their M700, BHK 300, DirectStream DAC, etc., I would like to see which graph/spec would be improved by using not the standard cord it came with, but the higher end ones they, or other companies, sell, disregarding EMI. You didn’t answer my questions...... Again, Can they, (harmonics), pass through the windings of a power transformer of a piece of audio equipment? Can they be radiated? How far? Specifically the harmonics created by, A light dimmer. Harmonics created by a switch mode power supply? Harmonics created by a full wave bridge rectifier found in the power supply of audio equipment? |
You’re not going to answer my questions are you?
Again, Can they, (harmonics), pass through the windings of a power transformer of a piece of audio equipment? Can they be radiated? How far?
Specifically the harmonics created by,
A light dimmer.
Harmonics created by a switch mode power supply?
Harmonics created by a full wave bridge rectifier found in the power supply of audio equipment?
Surely you know the answer!
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Both videos state it’s the harmonics, so not sure your point. Those are good harmonics aren’t they. Are you saying all harmonics are good? Harmonic distortion is good? DC offset, Harmonics), on the AC mains is good? NO, a power cord will not block DC offset on the AC mains. As for microphones, are you stating you are choosing your gear to make up the deficiencies in the recorded track? Where did I say that? Of course a $500 mic will be “cleaner” than a $5 mic, but don’t think that changing power cords or interconnects or speaker wire will negate any deficiencies of the microphone used in the recording. Timbre.... Who said anything about power cords. Will you hear a difference in timbre, quality, between a $500 mic compared to $5? I also very clearly answered your question, unless talking ground loops, your power amp will not be affected by a light dimmer switch or your neighbor’s refrigerator. No, you didn’t. . |
mzkmxcv351 posts01-14-2019 1:28pm@elizabeth
Hearing a difference is not the same as there being a difference. Say what?! // John Curl Interview Page 12/18 [Quote] Q: Okay, what about capacitors? JC: I learned how to measure a capacitor for the first time about 25 years ago working with Tektronix. They were making a piece of equipment which measured capacitors and they were really worried about the values. They were doing it with one of their pieces of test equipment -- It’s called a curve tracer. They modified it so it would measure the value of capacitors. They found that ceramic capacitors, for example, had another characteristic they had never been able to see on the screen before and it actually affected the measurement of the value of the cap. It showed a tremendous non-linearity. Interestingly enough, in this particular test and this method of measurement, only ceramic capacitors showed up to be really bad. We found that ceramic capacitors really were bad guys. Later we found that we could emulate the same problem indirectly using normal test equipment, but we had to operate the capacitor in some sort of real way. It couldn’t just be sitting there with zero volts across it; it had to be working with some kind of a signal like rolling it off high frequencies, low frequencies or something. John Curl Interview Page 13/18 I published a paper in 1978 and Audio magazine article in 1979 that showed this problem with ceramics, and we also found that Tantalum capacitors did almost the same thing. With this particular test (with normal test equipment) you could see the non - linearity of the Tantalum capacitors as well as the ceramics. This still allowed us, in theory, to use aluminum electrolytics -- we couldn’t find any real problem with them as long as they were used properly -- or any kind of metal film capacitor. A third type of distortion, which has been known for many years, but had been forgotten about, is called dielectric absorption. This particular problem used to be very important back in the 50s when people used to solve many engineering problems with analog computers. These analog computers would emulate mathematical equations with capacitors, resistors, or amplifiers. Music will also evoke dielectric absorption. Music tends to not be completely symmetrical at all times, and even though it averages out in the long run it isn’t necessarily a test tone. If you put a symmetrical test tone through a mylar capacitor for example you won’t find any real problem. However if you use an asymmetrical signal you’ll find that it does have dielectric absorption. This is where the dielectric absorbs part of the signal and then spits it back later. Well this can’t be good. Invariably you never get the musical peak, it cannot be completely passed by the capacitor because the capacitor has to take some of the energy from the musical peak. It stores it like a battery. Fortunately, this material property isn’t shared by Polystyrene, Teflon, or Polypropylene, which is why we tend to use these caps instead of mylar. Tantalum, aluminum, and mylar are pretty bad in this area. As a result of all this, we have to exclude many types of capacitors John Curl Interview Page 14/18 because they all have some problems to a greater or lesser degree. Ultimately we wind up with polystyrene, polypropylene, and Teflon. And that’s why we tend to prefer these capacitors when we can. Except for the use of aluminum electrolytic for power supplies , the more capacitors we can eliminate the better it its. Q: You’ve always been a proponent of trying to keep the signal path free of inductors and capacitors. Why is this so important?JC: It’s like this - it is easy enough today to design out capacitors between stages. It is rather redundant and wasteful to add capacitors between stages. First of all, they do not help the size of the unit. They’re not very reliable. If anything is going to go bad, the capacitors will probably go bad first ... unless you have catastrophic failure. In short, they don’t really do you any good so. The best capacitor is no capacitor...we don’t need them anymore. In the old days, when we didn’t have complementary circuits, we needed capacitors. When you look at vacuum tubes there is no such thing as a complementary vacuum tube device. So you almost invariably needed transformers and capacitors. Then again, one of the advantages of the vacuum tubes is that they are very high impedance devices, so the capacitors could be small in value even though they might have to be high voltage. Now, when you use capacitors in solid state transistor equipment, you generally need fairly large value capacitors, but their voltages don’t have to be so high. These situations would seem perfect for aluminum or Tantalum electrolytics. However, these are the ones that are not very reliable and they have all these secondary distortion characteristics ... John Curl Interview Page 15/18 dielectric absorption, nonlinear distortion, and that sort of thing. So, if you can eliminate these capacitors, why put them in in the first place? Now, some people can say ’what about leakage or safety or something like that?’ Well, of course, you have to be careful, and that is what modern protective circuitry is good at. It shuts down the amplifiers if they are behaving abnormally, yet it doesn’t impact the signal when the amp is behaving normally. We also use servos, which are basically very precise well matched IC devices. In the factory, they laser trim them down to one or two millivolts and then we simply use these to compare the output to ground and then adjust very slowly to zero out any offset that might be inherent in the amplifier or preamplifier. It’s easy to do these things now. Thirty years ago it wasn’t easy because we didn’t have FET input ICs, much less very well matched FET input ICs. For example, the JC -2 didn’t have servos because they weren’t practical in 1973 when it was designed. Maybe the military could’ve done it, but the real world had to wait until about 1978 or so. Also, we couldn’t use mylar capacitors, which are fairly efficient coupling capacitors. While mylars are fairly efficient from a size and cost point of view, we realized they have problems with dielectric absorption. I didn’t believe it at first. I was working with Noel Lee and a company called Symmetry. We designed this crossover and I specified these one microfarad Mylar caps. Noel kept saying he could ’hear the caps’ and I thought he was crazy. Its performance was better than aluminum or tantalum electrolytics, and I couldn’t measure anything wrong with my Sound Technology distortion analyzer. So what was I to complain about? Finally I stopped measuring and started listening, and I realized that the capacitor did have a fundamental flaw. This is were the ear has it all over test equipment. The test equipment is almost always brought on line John Curl Interview Page 16/18 to actually measure problems the ear hears. So we’re always working in reverse. If we do hear something and we can’t measure it then we try to find ways to measure what we hear. In the end we invariably find a measurement that matches what the ear hears and it becomes very obvious to everybody. [End of Quoted material.] http://www.parasound.com/pdfs/JCinterview.pdfSo first you have to admit you hear something....... . |
geoffkait13,658 posts01-21-2019 7:06am
, shielding on power cords doesn’t actually do anything when the rf is coming in on the conductor along with the current. Hel-loo!
Except the shield will stop EMI/RFI from passing through the jacket of the power cord and being induced on ICs and speaker cables that are in close proximity of the power cord. A simple test to check how well shielding will prevent EMI/RFI from radiating from a power cord is with a signal receiver probe. Just hold the probe next to the power cable outer jacket. If unshielded you will clearly hear the 60Hz magnetic field. You can also hear harmonics that may be on the AC line, like a light dimmer. Next conduct the same test on a shielded power cord. Depending on how well the cord is shielded there is a good chance you will not hear any sound, noise, from the probe receiver. Example of a Tone and Probe Tracing Kit. https://www.amazon.com/Greenlee-701K-G-Professional-Probe-Tracing/dp/B0042VII7A?ref_=fsclp_pl_dp_3
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geoffkait13,659 posts01-21-2019 8:27am
Of course, the real question is, is shielding on power cords per se bad for the sound, all things being equal? Apparently, shielding can affect the Sound when used for speaker cables and interconnects. Why not for power cords? From my limited listening experiences shielding can greatly have an impact on the SQ of an audio system. If not done correctly it can dull, for a better word, the sound. It’s like throwing a blanket over the speakers. To much sucks the air from the music. The same effect, from my experimenting years ago, with clamp on ferrites. And yes, that includes power cords. . |
Or if you only listen to elevator music.
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