andy2, An instability does not mean it has to oscillate, it could simply mean a settling issue, and to your point, an impact on the sound. And no, turnbowm, my experience accidentally making more of a capacitor than a cable is not a perfect example. Kimber cable is typically 30-100pf/foot, I think the higher Cardas is close to 500pF/ft. I was close to 100nF for a 12 foot length. turnbown, if there are no specific values for inductance/capacitance, then how do you know you were comparing cables with higher/lower values?
There
are no specific values/limits for inductance and capacitance because of
variables in the application. Your experience with amplifier
instability using high capacitance speaker cables is a perfect example. |
WRT:the amp + speaker combination will affect the sound as the cable capacitance gradually changes. It’s not something that happens abruptly, like a 90 degree cliff. Well, there is always the exception to "the Norm" - I know a guy that fried his Ayre amp and then fried a Gryphon integrated amp loaned to him - almost as soon as he turned each of them on. The first failure he put down to simple component failure, but when the second amp fried very quickly after power on he suspected something else was the cause - I believed it to be his TOTL Cardas speaker cables which had a very high capacitance. Since his system had worked prior to this event, we looked at what had changed. He had just upgraded the power cable on the amp, so we believed the Ayre had probably been teetering on the brink of severe oscillation for a long time - then he upgraded the power cable and Ka-Boooom! I believe the Gryphon fried almost as soon as he turned it on using the same cables. We surmised the "improved performance" of that power cable was likely "the last straw" for both amps. When we got the Gryphon back I loaned him some low capacitance speaker cables and all was well - but what surprised me is, the technician had never heard of this issue. High capacitance cables are only an issue with some high current solid state designs - I am told by many sources that tube amps DO NOT suffer the same problem. I have heard high capacitance cables might be preferable with certain amp/speaker combinations, but I have no experience of that. But this is something audiophiles with solid state amps should be aware of. I avoid high capacitance speaker cables for use with all my amps - just to be safe :-) Regards - Steve |
Well, there is always the exception to "the Norm"
Actually it's always analog. What you interpret as "abrupt" or "sudden" or "just like that", in the analog world, there is always some "transitional curve". The "transitional curve" may not be able to be "recorded" or "captured" by our perception or our ability since our brain cannot capture things like the oscilloscope can, but it's there. In order to have "just like that" in the real world, the energy required is "infinite". Like a step response, on paper, it's abrupt. But in the real world, there is no such thing as a "step response" since it would require "infinite" amount of energy. |
"....if there are no specific values for inductance/capacitance, then how do you know you were comparing cables with higher/lower values? "
atdavid,
I always buy speaker cable in bulk and terminate them myself. I use mfg's published data and, if they don't provide it, I ask. Below are several examples that I've used....
Kimber 8TC: Ls = 0.09uH/m
Mogami W3104: Ls = 0.6uH/m |
"....The first failure he put down to simple component failure, but when the second amp fried very quickly after power on he suspected something else was the cause - I believed it to be his TOTL Cardas speaker cables which had a very high capacitance...."
Goertz ribbon speaker cables also have high-capacitance that can be problematic to the degree that they offer a 'R/C Link' to combat amplifier instability issues. The R/C Link (aka, Zobel Network) is a resistor in series with a capacitor that is placed across the amplifier output to keep the demons at bay.
|
Originally patented by Polk 30ish years ago.
|
Any way you slice it, Noel Lee has a lot to answer for. |
mikepowellaudio88 posts11-18-2019 12:55amAtDavid and Dimora , Mi Casa es Su Casa for anything HiFi related. Its no trick of marketing , Im not smart enough for that. I’m sick of hearing this back and forth perpetual argument. I want to abolish it. I just offered anyone lets do this .. did you see how much interest there was in stopping the argument and getting to the bottom of it. ? Clearly nobody will come from overseas, that never crossed my mind. So you 2 are perfect, you guys dont know me and I will state for the record I dont think I know either of you, but based on moniker I dont know you guys.. So do either of you two have any $1000 plus power cords ? if so , we’ve got a shootout. If not, then you two are Audiogon forum users that can represent the AG Group for this thread. Keep in mind, I am a straight shooter. if something sounds better than my cable I will acknowledge it, furthermore if we become friends while you are here you must maintain an honest opinion even if you think Im a great guy and the other cable sounds better. Now if there is no $1K plus cable you can bring, then I need to know if you each are power cord believers or not, if you are , then come over any ways and we can listen to 3D Holographic imaging. Its a good reference point from which to judge other rigs, and its always fun for me to experience it in other peoples rigs because it is elusive. If you dont know what you think or better yet are a non believer that is OK with being converted to believer (if its truly heard) then come on over and Ill prove power cords work an a big way. There are some folks not willing to be converted , and that bias makes a closed mind, so its futile at that point. Every Friday is HiFi Fridays around here. I am in Smyrna by the new Battery Park if you google my username or just go to my username.com youll find my phone number to call and chat.. ame.com youll find my phone number to call and chat..
atdavid432 posts11-18-2019 11:23amI am there for work every 8 weeks approximately, but no guarantees on a Friday. I am certainly in. I don’t think it matters if me or Dimora is a believer or not, as long as you are. If you can pick your cables out blind (or between a basic shielded cable and yours) then you have proved they make a difference. I have a strong suspicion this exercise will go nowhere. No such meeting will ever happen. Prove me wrong. |
atdavid432 posts11-20-2019 10:10am"Originally patented by Polk 30ish years ago."
Matt Polk did indeed patent the use of Zobel networks in loudspeakers. That was in response to power amps self-destructing when using Polk's high-capacitance Cobra speaker cables. The concept of Zobel networks, however, was developed by Otto Zobel of Bell Labs in 1923. |
twoleftears1,947 posts11-20-2019 10:36am"Any way you slice it, Noel Lee has a lot to answer for."
What exactly should Noel Lee answer for? |
It is not a Zobel network, though it looks the same, it performs a much different function. A Zobel network is placed, typically across the woofer, so that as the impedance of the woofer goes up, the Zobel network simulates a constant impedance. That constant impedance allows the crossover to work properly. These were used in speakers well before Polk. Polk patented putting an RC-damper/snubber across the speaker terminals. The purpose of this was to dampen high frequency oscillations. turnbowm50 posts11-20-2019 2:14pm
atdavid432 posts11-20-2019 10:10am"Originally patented by Polk 30ish years ago."
Matt Polk did indeed patent the use of Zobel networks in loudspeakers. That was in response to power amps self-destructing when using Polk’s high-capacitance Cobra speaker cables.
The concept of Zobel networks, however, was developed by Otto Zobel of Bell Labs in 1923. |
atdavid, How is the series R-C network (Zobel) that is used to provide a constant impedance different from the series R-C circuit used by Polk to dampen power amp oscillations? To me, they serve a dual purpose. I thought you might find this excerpt from Nelson Pass's discussion of speaker cables to be of interest. ... "After a period of confusion, Matt Polk and I realized independently tahat the lack of a characteristic termination was causing the problem. Polk developed and patented a "damper" consisting of a .047uF capacitor and 6 ohm resistor in series placed across the loudspeaker, while I used the same network but with .1uF and 5 ohms. The results of this network are seen in Fig. 8 where the resonance in the pulsed waveform is damped out, restoring stability to an otherwise oscillating amplifier. Since Polk's commercial introduction of the damper circuit we have found it cures oscillation problems caused by the other exotic low inductance cables. It is necessary whenever a reasonably long length (>3 feet) of low inductance cable is mated with any wide bandwidth amplifier. It interacts unfavorably with twin lead conductors (Fig. 8) which require higher impedance values (say, .01uF, 60(2); however, twin lead's higher characteristic impedance and resonant frequencies are in any case unlikely to induce oscillation in amplifiers now available." https://www.passlabs.com/press/speaker-cables-science-or-snake-oil
|
For the same reason an RC-snubber across a diode or FET is not a Zobel network ....
|
atdavid438 posts11-20-2019 1:00pm"For the same reason an RC-snubber across a diode or FET is not a Zobel network ...."
They both have a resistor in series with a capacitor. To me, that makes them the same except for the name. I guess we'll have to agree to disagree. |
One point about high end cables: they all look a whole lot better than zip cord and Romex!
|
One point about high end cables: they all look a whole lot better than zip cord and Romex!
Agree! And this is a legitimate reason to spend $$$ on them. Nothing wrong at all with "looking good!" |
The capacity of Humans for self-delusion is apparently unlimited - Mr.Spock
Nicely said ... but here's the counter point. Mr. Spock himself is the product of human unlimited self-delusion. |
To All,
This topic most certainly catches the eyes of many who have already gone down this road and many that have not, I myself wondered and asked why so mush for what and I still haven't heard a specific clear answer. What I can say is that
Jay Luong's
27 Best Audiophile Power Cables has been one of the best if not the best attempt to put things somewhat into perspective in regards to the manufactures, models, and prices as well as what to expect at there particular value proposition.
Still today this topic seems to be unsolved I as well many of us still believe that much of whats out there is still marketing hype which again us as the consumers takes the risk of the product not performing and ultimately ending up in the guinea pig walk of shame closest based on many of the above comments in this thread. That being said I invited most all of the manufactures Jay
Luong
reviewed and even a few he did not to come to the table to set things straight to only get the age ole my cable is the best as a response along with some build recipes and or formula and why they are in there opinion.
Conclusion and Novel Thought for All:
I would think that by now it would be in everyone/s best interest if the manufacture would lay out what model should best coexist with what brand sound signature and what the consumer should expect to hear along with a 30 day total satisfaction guarantee as does only a few do out there.
|
Conclusion and Novel Thought for All:
I would think that by now it would be in everyone/s best interest if the manufacture would lay out what model should best coexist with what brand sound signature and what the consumer should expect to hear along with a 30 day total satisfaction guarantee as does only a few do out there.
+1
Report this |
Thanks to dimora and turnbowm for introducing technical analysis into this discussion of the benefits of high end power cables. I firmly believe that science should be the primary factor in deciding how lovers of pure sound reproduction should spend their money and set their priorities in making their purchases.
As I mentioned earlier, "I am very skeptical about the actual benefits of the host of fancy expensive power and speaker cords out there. The first thing I notice about the ads and write ups for these devices is the lack of any hard technical performance data - such as improvements in distortion, frequency response, damping factor and noise levels."
In terms of power cables,
dimora
correctly pointed out that the house wiring leading to the actual power cable could entirely negate any benefits of an elaborate cable shielding or configuration. In this situation, a power conditioner, coupled with quality standard cable would make a more sensible spending choice.
Electrical engineer turnbowm
could find no valid justification for large expenditures on power cables, other than assuring that the current carrying capacity was generous and the quality of the contacts robust.
My “Handbook of Instructions” for my Marantz Model Fifteen vintage power amplifier, makes no mention of replacing the “stock” power cords of this dual unit - and again recommends using ordinary 18 gauge lamp cord for speaker connections up to 30 feet and heavier gauges for longer distances. A unit of this outstanding quality, would surely have suggested using upgraded cables - if “perfectionist” audio designers Sid Smith and Dick Sequerra had any concerns about compromising its performance in any way!
I am again questioning the rationale - other than pure subjective judgement - of expenditures that could be better diverted to more quality electronics or mechanical components in the system. In that case, technical or scientific data could be fully employed to guide purchasing decisions - rather than vague claims by the cable manufacturers to justify their outrageous prices!
|
In that case, technical or scientific data could be fully employed to guide purchasing decisions - rather than vague claims by the cable manufacturers to justify their outrageous prices
+2 |
Maybe get NASA or DARPA, MIT, even AES to vouch for some cable or power cord. 🥱
|
@geoffkait
Lol Man, your off the chain! |
The problem with most cable claims, at least from the MFR claims is that they always work.
The argument w.r.t. the 50 feet of ROMEX before the plug sounds good and for some aspects of performance is valid. What it does not address is differential voltages between equipment locally, usually most influenced by grounds, though ground line interaction is possible. Do you need $20K of power cords to solve this? No, $100 of copper strapping between equipment grounds will do far more. There is the potential for power cord to interconnect EMI, but again you don't need a super expensive cord to fix.
W.r.t. speaker cables, inductance and capacitance can make some differences at high frequencies but so can humidity and likely larger effects unless you are running electrostatics in which case it would be significant. Gauge and inductance can make differences in response of 1/10s of a db depending on cable and speaker and varied with the speaker impedance. Audible ... Highly questionable and again, doesn't take $10k. And again, the claim that This cable will make all systems sound better is unlikely to be factual at all as results are highly system dependent.
Last, for all the magic claims, there really is no magic. Resistance, inductance and capacitance will be dominant, skin resistance can be ruled out quickly with stranded wire, transmission line effects only play when you have a very wide bandwidth unstable amplifier, and dielectric absorption is easily measured and quantified. Talks of silver, copper, cryo, geometry, etc. are just marketing to impress those that do not understand how meaningless that is, and that if those things really made a difference it would be easily measured.
If you do a search on a technical claim and it Only shows up hits related to audiophiles you know it is probably bull. Industries where performance means money or the difference between working or not (many scientific endeavours), and employ people who can track down sources of error, don't worry about these things.
One caveat is much expectation is that a product is designed competently. I can be confident my Rohde and Schwartz spectrum analyzer was likely designed properly or at least as performance parameters were properly verified. Boutique audio gear not so much. Many use linear power supply topologies that were state of the art 50 years ago.
Summary: I know pretty well how cables could impact results, don't believe most impacts are actually audible, know that some things that should not be audible are due to poor design, and know that no cable component can be universally better. |
What so-called magic claims by cable or power cord manufacturers are you referring to? I suspect you are making this up just so you can go off on one of your pseudo-scientist rampages, atdavid, Ethan or whoever. https://youtu.be/VEaLpslkwDE |
Well admittedly they are nothing like the magic claims you make for your products GK, but no one's takes yours seriously so ...... |
And what magic claims are those, Mr. Bluster? What have I done now? By the way, I knew you couldn’t answer my first question, the one about magic claims for cables and power cords. Because there aren’t any. Duh! For someone who doesn’t read my posts you seem a little bit obsessed with me, just an observation. My suggestion - take a long cold shower.
Side note - I broke two of your sacred laws of physics today and it’s not even dinnertime. How does that make you feel? Angry, I bet. 😡 |
For me DH Labs AC Red Wave bulk wire is a great cable with impresive price to quality ratio.
For about 130 US dollars you can have a VERY good 4 feet power cord.
Of course, you have to buy separately the plugs and make by your self, but its not a big investment to risk.
|
"
I firmly believe that science should be the primary factor in deciding how lovers of pure sound reproduction should spend their money and set their priorities in making their purchases"
I firmly believe that "lovers of pure sound reproduction" should spend their money anyway they please. What are you 12? |
I firmly believe that pleasure should be the primary factor in deciding how lovers of pure sound reproduction should spend their money... |
"....What it does not address is differential voltages between equipment locally, usually most influenced by grounds, though ground line interaction is possible. Do you need $20K of power cords to solve this? No, $100 of copper strapping between equipment grounds will do far more. There is the potential for power cord to interconnect EMI, but again you don't need a super expensive cord to fix..."
atdavid,
Good point. Circuit designers work hard to achieve a common (Star) ground point in their equipment designs and then we undo their best efforts by plugging the pieces of equipment into various outlets and power conditioners in the room without regard for establishing a common system ground. The Star grounding concept should be used at the system level and copper strapping is one way to achieve that.
|
atdavid: Not to worry about GK. Two things you can count on. One...he hawks this forum like a termite on a sawdust floor and will respond to just about any post within 5 minutes. Second...he will defend voo-doo audio magic as if you were challenging his heritage.
He is not a bad guy...just not one that believes science has any place in the manufacture of audio accessories; and offers personal insults in rebuttal.
|
dynaflex4 is a long-term know nothing and stalker. But he’s a good guy.
|
OK, so to respond to my post, I simply threw it out there, you may do with it what you want, but I am not afraid to double blind my cables. I dont think I have all the answers, I am not a scientist , I do believe there are things we experience as humans that can NOT be measured with any existing thingamajigger the physicists and scientists may have, even if it does go PING. The funny part is everyone is so stuck here. Its a phenomenon to me . Like we made a stick line in the dirt and put the chickens beak in it. The whole 50 miles of crap wire with noise, can easily be summed up so everyone can understand how a power cord could make a difference, in two words. . Filtering Cable. um....., is that so hard to imagine.. ? now depending on how much noise a filtering cable can remove will also affect the amount of noise on the ground plane of a piece of gear., this is because the safety ground is tied to the signal ground plane in 90% of pieces. Silly idea if you ask me , but I love differential design. Power supply noise gets on the ground plane from leakage current as well. This is why the more expensive gear where they have spent much time and effort at creating a low leakage, therefore low noise Psup , sound better and get less of a benefit from a filtering power cord. Ive decided to start really getting down to the nitty gritty if we want to talk cables. If people dont believe cables work, lets start with the microphone cable. to test this area, I recenty purchased a matched set of very flat measuremant microphones and a high fallotin mic pre. What I did not realize is that most if not all vocal mics have a rising frequency response in the higher frequency. Very simply put, the "coloration" starts with the microphone. .. this is a whole other discussion , but I ran recording tests this weekend with Mogami and My pure silver foil as a microphone cable . The difference is not subtle. Im also thinking a good way to prove the power cord thing is for me to make a power cord that will collapse your soundstage , in other words if power cords can change the sound of a rig, which they can. I should also be able to make one that degrades your sonic as well , right ? Yes , I can , through my trial and error proces, I know some things that will inherently degrade the sonic, collapse the soundstage roll off highs, kill dynamics, etc.. This may be easier for people to hear since it sits in the glass half empty arena and it seems some minds stay there.. So anyways , have a great Sunday and happy listening ! |
I should also be able to make one that degrades your sonic as well , right ? Yes , I can , through my trial and error process, I know some things that will inherently degrade the sonic, collapse the soundstage roll off highs, kill dynamics, etc.. This may be easier for people to hear since it sits in the glass half empty arena and it seems some minds stay there.. Perfect. +1 mikepowellaudio |
mikepowellaudio,
Making a power cable that is able to degrade sound does not prove that an audiophile-grade power cable will improve sound compared to a generic one of equal gauge. The only thing you proved is that you know how to make a bad power cable. |
blumartini What I can say is that
Jay Luong's
27 Best Audiophile Power Cables has been one of the best if not
the best attempt to put things somewhat into perspective in regards to
the manufactures, models, and prices as well as what to expect at there
particular value proposition. Well, if you think tests done with an utter lack of rigor or controls for his own imagination are "the best..." ..then I've got some magic health crystals to sell you . They are evaluated the same way. blumartini, have you ever tried to blind test between audiophile cables and a "normal" competently designed cables? (E.g. correct gauge for equipment etc). I have. It was very enlightening. When I knew which cable was in use I was sure the sound OBVIOUSLY changed. But when I didn't know which was being used, funny how those OBVIOUS ANYONE COULD HEAR IT changes vanished. Human perception and cognitive biases are pretty wild. The stance "If I heard it then it's true and my ears can't be wrong!" is a popular one among audiophiles. But it's up to you if you want to treat audio in essentially a form of religion or not. If so, have fun discussing how many thousands of dollars to spend on AC cables. |
prof, I suspect your results were because you didn’t implement the proper rigor and controls. Hel-loo! |
If you buy a $17k power cord I know everything. I need to know about you. |
Uh, noone in history has ever bought a $17K power cord. You’re barking at the moon. 🌝
|
@prof
Just for the record, I don't believe in snake oil, magic crystals, or pixie dust! But it does seem a lot do. What I see is the same ole same ole and nothing is changing. Had it not been for math and science we would still be in a cave.
Maybe Jay didn't have an exact science but it was most definitely a good starting point to something different than doing the same thing over and over and getting the same results, that is called "insanity". So other than magic crystals do you have anything you can bring to the table other than observation of the obvious? |
blumartini, What I wrote isn’t obvious to most on this forum. Most in the cable forum go on the "if I put it in my system and believe I hear a difference, I can trust that method to tell me the truth." And I didn’t see anything in what you wrote that suggested it was obvious to you. As far as I can tell you don’t voice skepticism about the standard audiophile belief that changing AC cables changes sound, and you have seemingly uncritically praised the Audio Bacon "tests," which doesn’t at all suggest you take the problem of sighted bias seriously. Maybe Jay didn’t have an exact science but it was most definitely a good starting point to something different than doing the same thing over and over and getting the same results, that is called "insanity". I can’t parse that paragraph. It’s not like Audio Bacon did anything different. They put cables in to their system, listened, and believed everything they think they heard. What’s different or a "good starting point" about that, in terms of moving the evidence for audiophile AC cables forward. They just took the standard unreliable method and did more of it. And in the article we find bald assertions like: Audio Bacon: Aside from practical (and legal) considerations, there’s also the type of solder, connectors, materials, and even technique used. All of these will determine the sound of a power cord. ...with no technical evidential support whatsoever. Not to mention this disclaimer right below that:
Audio Bacon: Blind tests are pointless for the same reason why the skeptics request them – your mind is always playing tricks on you. – Audio Bacon
Which is a statement of pure anti-scientific ignorance. You said you don’t believe in magic crystals, yet seem to uncritically accept results based on exactly the same method, a purely subjective "If I try it and think something happened, it happened!" Why do you seem to drop your critical thinking for AC cables and not new age healing crystals? I dropped in the thread because it seems you wanted a discussion concerning "The Truth About Power Cords." In which case, it makes sense to ask "where is the theory (that passes muster with other engineers) and objective evidence that AC cables COULD sound different, and the tests controlling for sighted bias that they DO sound different?" Or, if this is supposed to be a thread about "the truth" only for those who already have accepted the audiophile cable dogma? It seems that’s the case, so maybe it’s best I leave you to it. Cheers. |
+1
Anyone who makes such a comment about blind tests can't be taken seriously. |
Snake 🐍 oil is the lubricant for the tracks on which the train carrying Advanced Audiophiles travels. All aboard the advanced audiophiles train! 🚂 Toot! Toot! Remember the Little Train that Could. I think I can, I think I can, I think I can!
|
I have no objection whatsoever to anyone doing blind tests, which they probably don’t anyway, but results of a single blind test - or any test - have no meaning because so many things can go wrong with the test. It’s a complicated system. A lot of things can go wrong and affect results. A lot of people seem to think it’s a slam dunk and case closed. But that’s not true at all. Evidence is the accumulation of the results of many tests, test on different systems and by different persons. This is especially true for negative results, which is what the pseudo skeptics are prognosticating - negative results. Hel-loo! 🤗 |
@prof
I thank you for your input and for stepping up to the plate in this oscilloscope v.s. the ear discussion. There is much confusion out there when it comes to audio science, marketing and the ear and what you are saying about the mind playing tricks is true for alot of consumers. For the record, I do believe in science but at the end of the day it does have to process in the point of origination "the brain" and ears and thats why cable companies sell cables. At the end of the day it's the chicken or the egg theory. My hope for the thread was to somehow try to come up with a baseline that would bring the end user closer to their sound expectation at a reasonable dollar to science and ear other and not Marketing magic Crystal B.S. that drives power cord cost from $300.00 to $$.$$$.$$. And yes, at the end of the day people do rely on their ears as the ultimate science.
Thanks for your contribution:)
Cheers |
Many tests are not needed to disprove a claim, just one if the test matches the conditions in the claim and given how broad those claims often are in audio, or how specific they are, it is easy to replicate the conditions purported in the claim, right down to the specific test subject.
The great thing about blind testing is it isolates the auditory system as the exclusive "test". Really, that is all it does. It ensures that only the "ears" are used in the testing.
|
|
Oh look, a person who doesn't understand the concept quoting another person who doesn't understand the concept. I feel so much more enlightened now .... like at least 10lbs.
A blind test does nothing more than restrict the evaluation process to one thing, and one thing only .... your ears. It will never cease to be funny audiophiles claiming their hearing is so infallible that they must see what they are reviewing to hear it properly.
|
But what if the listener’s ears aren’t all he assumes they are and/or the test system is a hunk of junk? Follow? You thought this was going to be easy, right?
|
