Power Cord vs Power Supply noise who wins Part 1
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- čas přidán 23. 07. 2024
- This video 'Power Cord vs Power Supply noise who wins Part 1', I will show the waveforms at the input of the power supply - at even low input voltages to see the small things going on in the background. #powercord #audiophilepowercord #powersupplyinput
Below is the link to the power cable that I show in this video.
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All the hard science, evidence and common sense in the world will not convince them. I run audiophile equipment here, but i know what will, and more importantly what won't make a difference to my system. Fantastic demonstration and presentation. Keep up the good work.
You are right - but I may save the new comer from their greedy claws;) I appreciate you!
Love the explanation and demonstration. Added thoughts -
1. external high voltage spikes (from brush motors, heavy load switching, and lightning) can get through to the low voltage side via capacitive coupling between the windings so a shield can be installed in the transformer between the primary and secondary coils to minimise this. I found a need for this to stop lightning (ground strikes in the neighbourhood) from tripping the earth leakage protection when running power 250m away. Audio people may hear this as crackles on the output, and there are lots of pathways for these high frequency signal to get into a system.
2. voltage regulation has its place when running heavy loads, e.g., my farm water bore is 250m from the power and voltage drops happen. I got tired of the pump regulation circuit cutting off when the voltage dipped and, I over compensated... some thousands of dollars later I have 1% regulated AC voltage with an input voltage that can vary by over 60V, and it keeps the 2.2 kW load happy! Extreme, but effective, I'm not an engineer so over design is my default! My industrial unit was still much cheaper than an audiophile equivalent that could not deliver as much power. Of course someone else has already noticed fools and money resemble oil and water.
I love this feedback!! Thank you!! Oil and water - LOL;)
on the spikes to crackles:
I don't think that they'd be introduced through the power supply but much rather by coupling into the signal wires.
Now @@pjakobs you are being sensible and this topic was never going to be about sensible. 😉
In my power transformer example the spikes can come through and trip the earth leakage protection. In my audio amplifier they will never get past the voltage filtering and other engineering - shielded power cable never needed. But capacitive coupling from primary to secondary windings does happen and the system design may need to manage it one way or another.
@@user-xh9pt8zu2l yeah, sorry, I'm not the best reply guy trying to stick with the facts 🤭
Realistically any audio power amplifier that's supposed to be an IEC class II device with unbalanced inputs requires a shield winding (just make sure it's not forming a full turn, which would look like a shorted secondary and generate unwanted losses). Regular transformers in the hundreds of VA tend to have more parasitic capacitive coupling between primary and secondary than is generally deemed acceptable in such an application. (Let's not even get started on SMPS mains filters.)
If you see a hi-fi power amp with unbalanced input that's IEC Class I, I would translate that as "we're not selling enough of these / we're too cheap to warrant a custom run of mains transformers". (Transformers like that are primarily sold for the medical field, and that's pretty much it for off-the-shelf options.) Those lucky enough to not have another earth connection in the system are going to be fine, but the heresy of hooking up a computer (or a tuner with external antenna) is likely to be punished with ground loop trouble.
There have been some instances of nominally IEC Class II devices with excessive mains leakage... the larger Yamaha x60 series integrateds from the early '80s come to mind, which have sort of a dimmer type circuit in the primary side for voltage regulation and the hefty mains filtering to go with it. These were basically relying on a tuner to provide the earth connection, and if you let them sit by themselves they'll have a nasty hum on any open input. In this case it's fairly easy to convert them to "IEC Class II with earth" using a new 3-wire mains lead, a Y class capacitor of 2.2-4.7 nF and minor rerouting. The idea is draining mains filter leakage directly into PE, while the Y class cap connects PE and chassis. This way things remain safe to touch even in the unlikely case of a grossly miswired outlet, while the potential for ground loop trouble is kept to a minimum and the hum is obviously gone (a lot of what transformer leakage remains will be drained by the Y cap).
A similar approach incidentally is also applicable to some but not all switch-mode power supplies. Obviously it requires the luxury of grounded outlets, which a surprisingly large portion of the world is not guaranteed to have.
Thanks! Most interesting video. The older part of our plant was put in during WW2. Then in the 70s the DC plant bus generators were replaced with simple power diodes. Many devices did not like that modification. The DC generators had very clean pure DC voltage. 🤩 Anyway, thanks for the in depth power supply lecture.
Thanks so much for your generosity! I appreciate you. This is a great real life story;)
Super awesome video. Love all the explaining, it must be difficult trying to relay the technical aspects of what is happening in layman way so we can understand. Thanks for going through all this. 👍
Thank you! Yes, I do try to think about those without the depth of understanding. We all are trying to learn, so I try to show the same thing from different angles. I want anyone and everyone that wants to learn to be able to get that here;)
Toroidal transformers have a real shortcoming when it comes to inrush current. Since there is no airgap in the magnetic circuit (since it's tapewound) the core can easily get saturated in one direction resulting in a massive inrush current and circuit breaker tripping.
You often experience this with Variacs as they are toroidals.
Thanks for this feedback! Yes, large transformers can initially saturate and pull circuit breakers or damage other upstream devices. At times it is necessary to control the inrush current.
This was super useful, made me finally understand a couple things that have eluded me for years!
That's great - thank you!
Great video. Love the wave forms and the micsig scope.
Thank you! The Micsig is just so easy to use;) And their probes are excellent.
@@KissAnalog hey eddie quick question? when testing op amps with a DMM the reading between pin 4 and 8 should read open is that correct?
@@Amplified208 It depends. OPA1611 is single and pin 8 is not connected to anything. OPA1612 is dual and pin 8 is a positive supply pin (like in case of most/all dual opamps). NE5534 is single, but pin 8 is "External offset voltage adjustment/External frequency compensation". Some other single opamps are similar to 5534. So you need to check the datasheet I am afraid.
@jakubczajka4275 Yes, I thought that. I had a full rail voltage of over 35 vdc +/- go to Jrc4558 and Lm324n. On the Lm324n, I only have 124ohms between the supply pins. 😆 also, the data sheets don't tell you what it should read between the +/- rails, I would assume infinite. And other pins, you will get a voltage drop of a diode. I was just curious.
@Amplified208 It should read high ohms - and this is a great way to test to see if the OpAmp is shorted.
Thanks for the interesting video. I'm looking forward to part 2.
More to come! Thank you!
Hi Eddie, thanks for the great info. I loved it.
Thank you!
Right on man
Thanks!!
Tak!
Love your Rants about the hifi community misconceptions about power and cables. Maybe you can follow this video up with hum elimination in amplifiers and wiring methods of good hygene.
Kind regards. Kenni.
Thank you so much for your generosity!
Love the low freq switcher!
Thank you!
14:20 Speaking of rectifier diodes and EMI, traditional silicon jobs with sluggish turn-off need a bit of help in that department if there is any AM tuner nearby (or if the device in question *is* a tuner). Those have a habit of taking an incoming AM signal and modulating it at mains frequency, so a version of the AM signal with mains hum added is being rebroadcast (albeit weakly) courtesy of capacitive leakage in the mains transformer. Usually slapping anywhere from 22 to 100 nF across each diode quietens them right down - a common mod to make run of the mill transformer wall-warts suitable for use with portable shortwave receivers. A snubber across the secondary will have a similar effect as it dampens the secondary self-resonance which can be quite substantial in amplitude, but does not entirely address the problem at the root.
Thanks for your great feedback! I will cover filtering soon;)
Thanks for making this video Eddie! I am glad that you showed the fast narrow current pulses. Some people believe that the way the power cord "rings" because of these current pulses is one of the reasons that cords can affect the sound of audio equipment. And because the cord is closest to the equipment it rings more that the AC wiring in the house and out to the power pole. I wonder if there is truth to this?
Thank you! And - great question! In this video I am showing both the input current and the input voltage - so you can see if there is any ringing. I will show more of these waveforms;)
@@KissAnalog I did not see any ringing in your video. You have great measurement equipment. In the past I would have to connect a scope probe across the device under test to try and see ringing. I wonder if this was done to the neutral wire of a power cord, would you see ringing with the scope probe? I also wonder if a spectrum analyzer would show anything coming from a power cord?
You have great video's Eddie!
I love your videos, expertise, and insights, mate, but you've got to try to trim these videos down in length and make your points and examples more concise and in logical progression without repeating the same things over and over.
I know it's not easy, but there is HEAPS of competition on CZcams and other social media for our time by other content creators in this same space.
I hope you take this purely as constructive criticism and not just as some sort of "attack".
I truly enjoy and appreciate the information you present and myths you dispell, but it's often frustrating to sit through, especially when our time to watch such content is limited.
Cheers
Thanks so much for your feedback! I appreciate you! I will get better soon - I am really trying to learn how to do this. In this video there was a lot of set up - so the part 2 of this should be packed more full of info and less talk. Also, I'll try to hit the 20 min mark as an average. Is that a good time slot? Or more shorter vids?
Depending on system amplifier sensitivity & speaker impedance even changing iec from gold to rhodium can make a huge sound difference. Also adding pure silver can alter the impedance in wires but to hear a difference need a half decent system also good ears. Changing Power supply connectors make more of a difference to sound quality then changing rca cables or xlr cables.
Thank you for your feedback! I think I show how the power is mangled and then reconstructed to DC. The power connectors and type of metal just simply do not matter. No one has been able to demonstrate differently. Metals like rhodium will help against oxidation, but pull out all your power cables that have been in the wall or otherwise for years - is there any oxidation? Probably not, but if so there is very good cleaners/coatings that can be applied - but as long as they pass the current - it simply does not matter to the sound. No one can show that it does. The audio industry is full of snake oil and bad information. The engineering just is not where it should be.
For the ringing diodes backward into the transformer, I've seen use of RC snubber across the secondary but those can be hard to tune, the use of Schottky diodes as opposed to standard diodes might be interesting to see as well.
Great feedback! Yes RC snubbers can be used - but are also very dissipative. The diodes that are used on this board that I am testing are Schottky diodes;)
Very well done! It takes a lot of time and thought to construct and set up for this demo. Possibly in your next one you will show what happens when some sort of EMI filter is placed on the input side of your toridial xformer (probes before and after the filter)..? I envy all the equipment you have!
Thanks so much! Yes I do plan to show the EMI filter effects. I will do a video focused on just this - so to keep it shorter than this one.
@@KissAnalog I thought the length was fine. Possibly configure a way to connect one of those "Audiophile" AC cords in the mix would be fun too 😁
Thanks - I'll have to do that direct comparison. I think I'll do several videos on this as it also shows the power supply parts and operation;)
@@KissAnalog I am guessing you do not have a PS Audio Power re-generator nearby for more fun and game... Amir at ASR has tested of few of them as far as making any difference in a DAC's performance and any emi filtering they may do, if any, but nothing like what you have been doing with the AC waveforms. But you also have to make time to review all that equipment you accumulate 😄
The most "strange experiences" related to the power cord - are those cables that have 0.5 mm thick wires made of aluminum - I can tell you that those cables really are a disaster.
Thank you! I assume you mean in current handling - not some time of sound aspect at the amp??
Perhaps useful to show FFT of the current waveform. Probably shows harmonics all over the audible spectrum. That should scare them ;)
Yes-thanks! I'll do that in the next video;)
Nice discussion. Your homes wiring, the wiring from the pole to your home, all the crappy breakers, wire nuts, shared neutrals, etc. cannot be magically fixed by a 3 foot power cord with gold plug! For power conditioning, in some homes there may be some DC present on the AC line, there is a very simple DC blocker circuit for that. DC on the line plays havoc with toroid transformers, EI and split bobbin transformers don't seem to mind it. I'm still doubtful about much power conditioners, except for when you discover your home does have some DC present occasionally.
Thanks for this real world experience! It is literally nuts how some vendors explain now the last few feet - or they call it the first few feet into your amp - does make a difference. No measurements - even though they constantly refer to their engineering... It is maddening;)
Excellent video. I really learned a lot. Perhaps in the next vid there can be an explanation of the XL you were referring to? I have no EE background and am very mich a diyer. A. Ery knowledgeable diyer, but missing a lot of the core EE elements.
I have learned an awful lot from you Eddie, thank you.
Last suggestion would be to theoughout the video juat briefly put up a description of which color channel corresponds to which measurement. Its easy to get lost with the amount of information youre providing. This one is definitely a mulitple watch video.
Thank you!
Thanks for the great feedback! I will do a short video on XL and XC so that it will be short enough that more people can take the time to watch this video on such an important subject;)
@@KissAnalog thank you! You're demeanor and straight forward attitude is was keeps me coming back
Whiteboard diagram mekes it easy to understand for me.. thanks...
Thanks for your feedback! I'm glad that helps;)
Back when I thought there might still be something to using thermionic valves in guitar amps (tl;dr: there is, but it's not perceptible) I ran across the idea of using snubber capacitors across the diodes in the rectifier to reduce ringing. Would that also reduce current noise?
Great question! Yes, snubbers can help minimize ringing - but the best bet is to switch with low ringing to begin with;)
I would've thought the fact that the power transformer primary is decoupled from the secondary would be enough proof that an Audiophool power cable cannot make a difference to the sound.
Thanks for this feedback! The inductance of the transformer is so much higher and the secondary is isolated (but they are coupled tightly). I'll go over this more in depth;)
@@KissAnalog Oh I see,look forward to it.
Hey another interesting video from you thank you. I have to admit that I am into the Hi-Fi audiophile sphere, and that I think and I have perceived some differences between different cables, signal and power ones, which offer different sound characteristics and different background noise or noise floor level. But I have to admit that paying thousands of dollars for a cable it's really really something that's very hard to justify, okay I admit maybe some few hundreds for a 5 ft or 8 ft power cord is reasonable, but really going over the thousand mark for a cable cord of this length is something I will never go I simply call it Hi-Fi jewelry most of those very fat cables are mostly dielectric and air inside but also when you consider that all the variables that are inside a amplifier or any audio gear and you see capacitors, resistors, diodes, PCB's copper tracks and inner cabling then you know it is kind of nonsense to try to fix all just on one side of the eq. adding an expensive power cord.
Thanks - I think you hit the nail on the head. There's just too many other more important things to get right. I agree, a nice looking cable does look great connecting things together;) But, when it comes to power cables - I think a certified safety cable is more important;)
caveat: I've only seen the first half of the video but ... (famous words of any opinionated reply guy on the internet)
when I hear "linear power supply", I don't mentally go to the transformer and rectfier but to the linear reg, iE the 78xx / 79xx and I would say that, given enough voltage headroom on the input side, their output should be better than what comes out of the bulk capacitor stage of any rectified/switched power source. If I do digital 3.3V designs nowadays, I usually build a primary to 5V switching converter and follow it with a 3.3V linear (like an MCP1700-33) to make sure a drop in the bulk capacitors doesn't hit the device.
In that case, as long as I have really low resistance and inductance between the regulator and the bulk capacity, my 3.3V should be as good as ever possible with a minimum of power dissipation (~500mA peak at 1.7V - less than 750mW max)
But for the demonstration of the non-effect of power cord quality on the output, looking at the front end of a power supply is of course perfectly sufficient.
Alas, no audiophile will ever watch this.
pj
Thanks for this fantastic feedback! Yes - the 'linear' comes from the regulation stage. Many Audio Power amps - or even most of them do not regulate the power stage - but yet they are referred to as 'Linear' power supplies. I'm just trying to 'straighten' this up once and for all;)
@@KissAnalog ha! And just there, I learned something. I looked at the schematics of my old Sony Amp (remember when electronic devices came with full schematics?) and indeed, the +/- 45V that drives the final amp stage is unregulated. I did not know that.
Now granted, since this stage should stay away from the rails, voltage ripple on the rails should not be a problem as long as they can supply the current without dipping into the signal levels.
I really was not aware. Thanks!
[edit] but: this really goes to show how absolutely nuts this "audiophile" power side woodoo is. Noise on the 115/230V AC rail on the input matters a rat's ass to the power amp as long as it can supply the required current*voltage product with the required transients.
A friend of a friend has tried to convince me for a full evening of the benefits of "proper power equipment" at a party a few years ago. Should I be so unfortunate to share a table with him again, I'll have some more data here.
In a way, it's so sad that those people are being taken for a ride by the manufacturers. But at the same time: what can you do if the people being sold snake oil really really believe in snake oil?
[end edit]
Btw, my theory is that some of the best mass market HiFi equipment was made in the late 80s/early 90s. By that time, people had figured out how to deal with the much better but also more demanding signal from CD and there was enough money in the market to have a good base of electronics engineers who really understood audio.
The 5.1 surround wave that came later was probably not helpful for HiFi as it was more geared to what the movie folks needed and after that, music consumption trended towards pure convenience where small size and portability became more imporant than sound.
I am still not sure what to think of class D amps - despite the fact that most of the electronically reproduced sound we hear today is from a class D.
Would using MOSFET 'ideal diodes' for the bridge rectifier make any difference?
Still think the way to go for the money-no-object audiophile crowd is batteries. It should be possible to build a transparent mains PSU using batteries as a component to completely isolate the output from the mains. Build a box with four high voltage lithium batteries, at any time two will be in service providing positive and negative rails for the amplifier and the other two will be isolated from the amplifier and being charged from the mains using a high frequency switcher. Arrange for an automatic switch-over as the in service batteries become depleted and we have a completely automated system with a perfectly linear, fully isolated, DC power supply. Probably the difference is imperceptible, but it would at least be measurable!
I had a technicsl pre-amp that had an internal battery. As soon as you turned it off it would start charging :)
Great question! Using a MOSFET would still result in the current spikes, but the MOSFET Would be more efficient with lower voltage drop. Using Batteries for a test would be interesting. I think I now have enough lithium batteries to do a 24 V rails.
Hi again i watched your second video and firstly from your reply im not anymore biased than yourself i said i went into rhis not believing power cords could make any difference to the sound also i didn't invest anything and repurposed a scart cable for AV that had silver plated copper and heavy multiple shielding the 1st one i constructed was heavier gauge and better purity copper and made no difference whatsoever but the second one with heavy shielding was night and day and there are enggineers that are on the other side to yourself also i watched another engineer trying to prove that mains conditioners don't work and hooked up measuring equipment to the outputs of the amplifier with and without a conditioner one made no difference but one clearly showed on the overlayed graphs that it indeed was filtering noise on the outputs a lot of I listened to that i had no investment in actually made the system sound worse. Another thing you mentioned your measing equipment comes with standard power cords, shunyata research developed their power cords for medical measuring equipment and shoqed graphs showing the increased resolution of the equipment when the noise wasn't present i would of thought the bean counters for the hospitals would not splurge money on these things if there was no merit. Im interested to know what audio equipment you used and power cables you tried that didn't produce any change good or bad. On a final note some of the prices that are charged for cables are ludicrous and some of the tom foolery in the tweak industry doesn't help credibility like a $5000 fuse and i can only form an opinion based on my experiences anyway debate is healthy and i wish you the best thanks for the video's
Thanks for your feedback! Much appreciated! Power conditioners do clean power for sure, but the question is; how many of us would need one or benefit from one? The company selling fuses should not be trusted unless they are UL approved - IMHO. This is a safety concern. Also a hospital power cord has to meet certain safety criteria and has to be certified.
If the difference can't be measured but "can be heard" it's just in your head and if the difference can be measured but can't be heard its pointless
If someone truly believes they can hear a difference and they love the sound because of X does it matter to them if its real or imagined? I don't know 🤷
I guess it matters if they start passing it off as fact and that others can/should expect the same results 🤷 but I was thinking more just on a level of personal listening experience
IMO ALLEGEDLY
"can be heard if known".
there's people who think they can hear the difference if a wav file was previously zipped or rarred.
I think you covered it quite well;) Thank you!
Wow - but can they do this in a double blind test??
While I like today's video, it's a bit sad you have to make it. Overall I was more interested in a review of the Itech Programmable AC supply, I've been looking at getting one of those for a while.
Thank you! I will do a review of that power supply in a few days. I am using it for this video and the one that I am working on now. I'm getting a good feel for it so that I can properly demonstrate it;)
Would it be considered a linear power supply if you had a auto--transfer instead? So as of the result of increasing the ac voltage the dc voltage also increases. It's still noisy from the bridge rectifier, but was wondering if that meets the definition of a linear unregulated supply?
I think the video and my experience would say the same thing... "linear power supply" is a label, not a definition. Don't remember the term being used until switching power supplies were common. Before that it was just the power supply. And, it's not linear if the voltage out varies with the voltage in. That's just unregulated to whatever degree, and mostly undesirable. Times have changed... in days past there were problems with the switch mode frequency showing up on the power rail and potentially affecting output. We now have components good enough and cheap enough that switch mode designs can outperform many transformer designs for less money and way less weight.
Thanks for the great question! Linear is a term used in regulation. If it is Linear - the regulating device holds the output and blocks the input continuously - which is considered linearly. Conversely a switcher turns on and off to regulate the output. Does that make sense?
@user-xh9pt8zu21 Yes I think you are correct. It is just bad labeling;)
My power cords are hand made by Sir Lucas at the British Leyland factory. 😁
Noooo run away;) LOL Thanks!
Is that big toroidal transformer silent? Or can you hear a hum coming out of it?
Great question! This transformer actually does have some hum. It was labeled with Hum and that was why it was rejected by the manufacturer and this is why it wasn't sent to Dynaco. I think this could be solved with more potting if I wanted to use it in an actual design. Did you suspect it because of the size?
I suspect it, because long time ago I used to use 250VA toroidals to power up tube amps and every single one of them was humming (annoying when you are listening quietly in the middle of the night). Recently I have purchased a bench supply powered by some 350VA toroidal, and it is humming of course. It is one of the reasons why I do not want any big, unregulated and NOISY power supplies. 50/60 Hz large transformers are maybe suitable for guys who can "hear" differences between power cables.
LOL - yes I agree! Some audio companies who knew that they needed to hire actual power supply engineer/s have switched to switching power supplies to get rid of power supply noise - go figure;) You can't hear a switching power supply;)
I lift my power cables up high, so the current really flows well into my amp. It seems to give me an extra 2hp. Lol
LOL - this is perfect!
How does this relate to the $200 power cord? I think you have showed this particular demo multiple times.
Thanks for asking. I have shown these waveforms in different context but this time I am showing how significant the waveforms are being processed as they go thru this part of the power supply. Then inductance of the transformer completely swamps out the inductance in the power cord. I will show in videos to come more about the power supply and how a power cord cannot make a difference. But in all this - people will learn how a power supply works at each level.
There is a market for highfalutin power cords, but it should shrink as people wise up, and realise that they are being taken for mugs by unsrupulous and exploitative snake oil suppliers.
I agree - thanks! It is fine to spend the money if you understand why you are spending it and not thinking that you need to for better sound;)
I might be cynical, but in recent years, I have not seen sings of people getting wiser.
The sentiment of "stay away with your science, I have my own sources I trust" is strong in many fields and in a way, it's only fair that the free market takes them for a ride.
It's our duty, though, to call them out so influencible people have a chance to hear about the science and can decide if they want to go on that costly ride or not.
Add aFerrite coil
Thanks Kerry! Do you mean to the power cord for high frequency filtering?
Eddie this Video is Toooo Long!!! (Just Kidding) some topics need details thanks!!!
There are some rare cases 10-50millivolts swing can improve sound because it all lives in the microvolts & milliamps for (analog & digital)
LOL thank you!
I get what youre saying,but like in food, there are super tasters ,i believe theres the same thing in audio, and just because our instruments cant pick it up doesnt mean its not there. Thats another thing, your using insturments to view reality but forget the best instrument the universe has produced, better then any of our inventions - us. Our ADC is way better then anything you can buy or make, so i do believe someone when they say they hear something. Obviously theres a lot of placebo effect going on, but like they say dont throw out the baby with the bath water. I believe there is something audiofiles are hearing. Wether its worth the price thats not my decision but it does seem like a waste of money, but thats the root of another problem, jacking things up 10000% because of a 0.000001% difference , that mentallity is whats really wasteful in the end. I complain how much money is spent on defense vs trying to explokre the universe yet we waste just as much money or more on frivilous things.
Thanks for your feedback!
Here's the bottom line - no one has shown that they can hear the difference in a double blind test. I have not seen or read one single report that someone can do this. No golden ear - not a single report.
There is nothing wrong with washing your car and putting an expensive wax on it and thinking it runs better:) If you like it clean - that makes you happy - then great - it runs better:) But don't try to sell the wax and charge 10x or 100x for it and make others believe it runs better. That's what I'm trying to show - the difference between belief and science - or physics.
I will keep testing to see if I can find something - anything.
I will have to disagree with you to certain extent, you can't hear differences I can I think it's down to the capacitance and the inductance even in the pico ferrets I have experimented with changing these around and yes there is a difference you can hear I don't believe it's Placebo either because sometimes things you change around don't sound as good even down to interference between power leads crossing over each other I think you need to experiment go to a high end store with a million pound system and see what happens don't forget to take your measuring equipment lol
@jedi-mic
And you have conducted 100% unsighted/double blind, level-matched listening tests to confirm that you can actually discern these differences at least 10/10 times in a row to eliminate any factor of pure random chance, correct?
I urge you to search for and read this short blog by Dr. Sean Olive, PhD, of Harman/JBL that will take less than 5 minutes of your time:
"Audio Musings by Sean Olive - The Dishonesty of Sighted Listening tests"...
sean.olive.blogspot.2009.04
Depends on the ratio of nanominks to microweasels per square beaver area
Hi @@paulb4661 are you saying this is all about pico mammals per pelt? 😄
Thanks for your feedback! Double blind tests are not published because power cords do not make a physical difference - but they can make the person that likes the look of the power cord to enjoy their system more. That is the placebo and it is real and it easily describes the explanations that people provide that say that they can hear the difference.
@@user-xh9pt8zu2l Probably yes, but I was never that good with maths! 😉
I just watch several of PS Audio vids. First impression, all he does is talk. No scientific analysis or technical demonstrations of electrics or physics. ALL HE PROVIDES IS OPINION. I saw no testing with any real numbers of any phenomenon substantiating any of his claims. PS AUDIO for Audiofools. My buddy talks about the old Kung Fu movies and how these guys are so powerful and get energy from their inner core and other crap. I told him why isn't Einstein's theory E=M*C2*Inner Energy but its only E=M*C2? OR Kinetic energy is1/2 M*V2 instead of 1/2 M*V2*Fung Schway.
LOL - yes PS is mostly just talk. I think they put Paul in front of the camera as he is a nice enough guy and let him talk - as they really don't have much science to their equipment IMHO;)