Getting what you want

January 24, 2019
 by Paul McGowan

When we set out to prove one thing or another we arrange tests to prove our theory.

For example, if you’re trying to prove there are no differences between cables or amplifiers there are any number of ways to prove that. One would be the difference or null test where an identical signal is passed through two samples: say an expensive interconnect vs. a cheap one. If there were actually a difference it would show up on the scope as such.

Since we know that changing input cables—a high-end version vs. a dimestore copy—on a power amplifier in a highly resolving system is easy to hear, the null test should show the difference. Yet, it may not. Do we then conclude there are no differences?

If our goal is to understand why we hear a difference then it’s incumbent on us to dig deeper. Our hypothesis didn’t give us the results we were looking for. Our ears detect a difference our meters and methods fail to uncover. The proper conclusion is not to stop there but to march forward until it can be satisfactorily explained.

Garth Powell of Audioquest proposed a method that just might have some answers. Since the change we hear comes out of the loudspeakers and affects the entire audio chain, it’s only logical we measure the entire chain to seek differences. This would involve using a microphone to capture the output of the system and then comparing the recorded files to find the differences. It’s essentially the same test I have done any number of times with the microphone in my iPhone which more than adequately picks up differences.

I haven’t the time nor the interest in performing these tests with any scientific rigor, but perhaps someone else wants to grab the flag and climb the mountain. It would have to be performed on a system where we actually do hear a difference.

Proving what we already know might be valuable to someone.

Just not me.

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41 comments on “Getting what you want”

  1. Paul, it appears that both Mark and Ethan want a piece of you, how flattering ?

    Who Can You Trust – The Ongoing Battle

    “And then there’s the battle going on between Ethan Winer, the author of “The Audio Expert” and Paul McGowan of PS Audio. As many of you know, Paul has written a lot about high-end audio and lately he’s been producing a daily video where he talks about current topics in audio. I know Paul and regard him as a knowledgeable person in the audio world. I’ve visited him in Colorado and seen his operation AND I’ve owned some of his equipment over the years. But I have to agree with Ethan on this one. Paul says things that aren’t true. I’ve written about some of his misinformation (and I’ve also chastised Ethan for his high-resolution test). Again, it comes down to trust. In general, you want to stay away from statements made by manufacturers, magazines, editors, reviewers, buyer’s guides, and videos that benefit directly from the information they provide.

    I’ll write about who you can trust in a future post.”
    Mark Waldrep – 19 January 2019

    Why anyone would trust and take this pompous db’s advice is beyond comprehension …

    “Those of you who backed the YARRA 3DX 3D audio sound bar and have been patiently waiting for delivery have only a little while longer to wait. How do I know? Another year is almost over. I’ve struggled, fought the good fight for the YARRA 3DX 3D audio sound bar (but ultimately failed). Altan, Richard, and I discussed the market for the sound bar, challenges bringing it to market, and the current situation at Comhear, the company that ran the crowdsourcing campaigns. I was hoping it would be the YARRA 3DX but perhaps a new venture will have to take the lead.”

    https://www.kickstarter.com/projects/yarra3dx/yarra-3dx-the-most-advanced-3d-audio-system-in-the/posts/2337642

    1. To me the whole discussion including the “who can you trust” question is as if we’d discuss the color of greenwood and a riddish wood with various color-blinds. Why would I have to “trust” anyone of them or not if I can just judge myself if the greenwood is green, reddish or grey for me?

      Why should we spend our time with various color-blinds explaining and convincing us why the wood is green, grey or reddish and try to “measure” what the color really is if everyone’s happy with his perception? Because people want to have a point. And the more difficult it is to prove/measure something (audio being the perfect example), the more fun it seems to be for people to argue about what one hears and the other one doesn’t and who’s right. What a silly activity.

    2. When I first started reading Waldrep’s newsletter he was mostly talking about 24/96, and his recordings. When he was talking about hi-rez needed to be consistent. That made sense, although I disagreed with him on whether transferring analog tape masters to DSD or 24/96 could be considered as better than redbook.
      Then he started preaching on his bits are bits soapbox.

      Now he sounds like a bitter old man. He has been removed from various audio boards, and no longer asked to speak at seminars, or audio shows.
      And the Yarra deal hasn’t helped his credibility.
      I have heard that even when he has heard differences he will not accept the results. In his, closed mind, it has to be something else, and I think that is why he is no longer welcome. Of course he does have his loyal followers. As does Paul, but while Paul is sunny and enthusiastic, Mark is a walking storm cloud, alienating more people with each newsletter. He no longer supplies a link for comments. You have to go to his website and find it.

  2. I rather regret not going to Mr Powell’s demonstration recently at my local dealer, advertised thus:

    “Garth will offer a brief history on AC power and speaker cables in various high-end audio applications, before launching into the music. Guests will experience AudioQuest’s Niagara Series, Storm Series AC cables, and the highly anticipated Mythical Creature speaker cables through a world-class system featuring the stunning Focal Utopia Scala loudspeakers and flagship Soulution amplification.”

    I agree with Paul that if it sounds better then it’s all fine and dandy, no need to know why. That. however, is only the consumer’s viewpoint. A manufacturer of a product with any engineering or scientific credentials should set out with an objective, a plan to achieve it and then test to see if it has been achieved. The ultimate example is the development of synthetic drugs for medicinal use, evidenced by the extent to which the market is regulated. No one wants to know how a drug works, just whether or not it will cure them of their illness.

    On the other hand, consumer companies build up brand value so that they can sell you a pair of sports shoes for $150 that have a manufacturing cost of $10. They don’t claim to give you healthier feet, just more fashionable ones.

    So it’s a matter of substance or style and I would hope that consumer audio is more about substance over style. Hence Paul should be very concerned about design objectives and measurements when making amplifiers and marketing claims when selling them, just as Mr Powell should be with his power products and cables.

    My big grumble is that most engineering-based developments in consumer products seek to produce better products at lower cost. Many newcomers to audio do this, whether Chromecast or Schiit, whereas plenty of longer-in-the-tooth top end audio companies just make increasingly expensive products based on wilder and more extravagant claims. The ultimate proof is cables, because a rational designer would set an objective to make a cable that costs $500 that tests as well as existing cable for $1,000. They would then aim to make it for £300, then $200 and so on. Instead, they say the $1,000 one is OK but you really need this one for $2,000. All unsupported by any objective and verified engineering. At that point it is simply a banded fashion product.

    I am not suggesting this is universal, and many manufacturers will do both, because the profit margins in cables are astronomic and pay the rent. I doubt I will ever live to see the day that a cable manufacturer announces that they have designed cable B that is as good as cable A and because we did the research it costs half as much. Someone prove me wrong.

    1. Hello!
      May I tell a little episode at this point?
      Two years ago, I participated in a demonstration of very expensive power cables that was made by an employee of a manufacturer of expensive accessories and cables at a dealer that sells almost exclusively high end audio products.

      The power outlet was about 4m away from the components rack. Therefore, a 5m long wickedly expensive power cord had to be used to reach the rack.
      At first the discussion started as usual: “There are only standard cables in the wall, why do I have to use these expensive cables when I want to connect them to my devices?”
      The manufacturer’s representative replied that just ONE meter of the high-end cable would change the sound for the better. When I asked why one would not simply use a standard extension cable to which one could then connect othe 1m cable of his company, I was asked to leave the event. So much for the readiness to deal with the questions of critical customers.

      No two cables are identical, not even the same type of cable from the same manufacturer, or has anyone ever counted the number of atoms and thereby calculated the free electrons in the metal grid? If we assume that the different cables sound different, then it is only due to the lack of quality of the measuring apparatus, if these differences can not be represented metrologically.
      B.

      1. Why should a cable manufacturer disclose his proprietary know-how and allow competitors to copy his ideas? It’s the job of the marketing guys to invent a story or a myth which might create awareness and convince customers not trusting their own ears but being liable to fall into the trap of cognitive bias effects. The funniest thing are stories told by some tweak manufacturers claiming neutrino effects or “harmonization effects” on the ambient air improving sound quality. But on the other hand the proof is in the pudding. How can you get a finding on cable or plug effects only referring to a theory based on massive assumptions and simplifications? If our existing theories would completely explain nature and the universe research wouldn’t be needed anymore.

        1. It may surprise some people that if you invent something and seek to patent it, you actually have to describe it and how it works, together with evidence that it works.

          I once saw a patent approved for a cable. It was based on a poor description and very spurious tests. The patent clerk was obviously having a bad day or was distracted by something, possibly grappling with the fundamental laws of nature.

          I googled “patents audio cables” and, for the amount of claims made, there are precious few patents.

        2. I think it’s important when any manufacturer in any industry claims superior performance to reveal their design and materials engineering technology to validate their claims and price points.

          Two companies come to mind, the first is Ed Meitners EMM Labs DA2 Reference DAC where they claim their MDAC2 to be the world’s first true fully discrete DSD1024/16xDSD D/A converter, still built in-house because we’re not willing to accept the inherent non-linearities of every mass-market chip created to date. Yet there is absolutely no disclosure in terms of the actual circuit architecture.

          The second is Kubala Sosna, who along with several others build outrageously priced audio cables but offer zero information on their design philosophy, materials and construction techniques, any system applications guide or music performance advantages.

          All they state at their website is “we are pretty proud of our technology, even though we do not talk about it all that much.”

          The most straightforward audio cable designer imho is George Cardas. George is a good man, gifted, talented and offers the most authentic approach to market in terms of design and engineering rationale and performance. They just lay it all out there for folks to clearly see what’s going on inside the product. Further agree that until one actually listens at home to a recommended cable in their system does it have any meaning as to how it relates to music.

          In the world of expensive and often ridiculously overpriced high-end cables, Cardas Audio delivers real world value and performance. I purchased several based on their music performance.

          http://www.cardas.com/insights.php

        1. dr. goodears
          They literally said: “Your question does not contribute to a better understanding of how to improve the sound with our power cables. We think it’s better if you leave now.”
          That’s probably enough to see how “Transparent” their technology is and whether they are serious about informing their customers.
          B.

  3. I remember reading Stereo Review back when I was a teenager and how Julian Hirsch asserted that all amplifiers that are competently built and of the same power (if I remember correctly) would sound the same. At the time, I believed him but also wondered why Stereo Review didn’t just list the least expensive competent amplifier at each power level once a year and quit reviewing them since they “all sound the same.”

    Fast forward a few years and I bought a used Adcom preamp and 100 watt power amp (GFA-545). I only needed the preamp, but the seller wouldn’t split them. So, I brought them home and hooked them up. I first inserted the amplifier to see if it was working before I tried to sell it. I didn’t expect to hear any difference as I had been instructed, but that 100 watt Adcom amp kicked the crap out of my 200 watt BGW professional amp. The more expensive BGW went packing and my high-end days began.

    More recently (25 years later), I changed out some long-term medium priced highly regarded speaker cable for some old Kimber 8TC I had forgotten about. My wife came downstairs to listen to music with me and quickly asked, “what did you change – it sounds deeper and wider?” The two cables probably wouldn’t measure the same, but can simple Ohm’s law measurements reflect a change in the soundstage?

    1. @stevevollmer – this is where probes at both ends with the inverse sum math function on the scope can show, or usage of Lissajous patterns can expose. I don’t think I would use a mic to evaluate this, since you introduce the mic’s curve and response into the mix, which can muddy the waters…

    2. In my early days, I too read, and believed Julian Hirsch. I was very proud of the fact that my amp and preamp came with their own measurement tests. The specs are great, look at those low distortion numbers, that was 1973.
      It wasn’t until 1993 that I saw, and bought my first copy of Stereophile. It changed my whole outlook on what mattered, and that is everything.
      The horrible sounding preamp, and the mediocre amp, that I sold, then got back, when the friend died, which I still have it, still works. The preamp died many years ago, I sold it to a dealer for it’s parts and the wood cabinet.
      Those, great spec products were a Crown IC150 and D150.

  4. Personally, I’ve never found an obvious difference between power cables. Maybe that’s because the ones that come with good high-end equipment tend to be up to the task. On the recommendation of a couple friends in the high-end business, I bought a WAudio power cable from Amazon for $35. We compared it to a $10k+ power cable (on loan from a manufacturer, because who in their right mind would buy that?). We didn’t hear a difference. Maybe we heard no difference because that made us happy; human brains are rationalization machines, not measuring instruments.

    https://www.amazon.com/dp/B01L2MBYWC/ref=psdc_3236443011_t1_B077J98CJ4

    1. The snarky answer: Your system wasn’t expensive enough to recognize the pedigree of those expensive cables and you should be arrested for degrading those wonderful cables by connecting them to inferior equipment.

    2. @eatapc – The primary concern for power supply AC is that you have enough current to satisfy the amp’s needs. (which large gauge cable can help) Common mode filtering in power conditioners is not your friend in high current applications. AC noise in a commercial environment is generally not experienced in the home setting, and EMI at low frequency cannot and will not be handled with shielding, as EMI @ 60Hz (the greatest interference issue) passes right through.

    3. I have had some of these power cords queued up in my cart on Amazon after seeing mention of them here or elsewhere. I am planning to give them a try. Maybe my system is not fancy enough either to hear the difference but it’s good enough for me and I will remain happy!

      I started using a lot of KabelDirekt products from Amazon as well and have been very pleased with them. I traded out all my old interconnects for their products in the last year and remain happy. The HDMI cables have performed much better than my old AR cables which were quite expensive when I bought them and highly rated.

  5. “If our goal is to understand why we hear a difference then it’s incumbent on us to dig deeper.”

    Excellent idea. Here’s a question about that? Why is it that when you compare the sound of the New York Metropolitan Opera singing at the Opera House to the sound of Infinity IRS or any other speaker for that matter, the sound from the speaker sounds like canned music?

    “I haven’t the time nor the interest in performing these tests with any scientific rigor”

    Welcome to the high end audio industry.

    BTW, do you think it could be that the IRS just can’t play loud enough? Maybe you need a second pair.

      1. I love teasing my friends. Jealous? Now why would I be jealous? Would I trade my system for yours? I haven’t heard yours but you have heard mine and it does not sound like canned music. I wouldn’t trade for anything. It sounds exactly the way I want it to. Any change would be a move downwards as I see it. There have been no changes since you heard it and as long as it is not beyond repair I intend to keep it exactly the way it is. As you know I have a lot of rooms in my house and can set up as many systems as I want to. I can also afford to buy anything I want to. New audio equipment is not on my list of priorities of things I want to spend money on. At the rate I’m drinking wine I think I have enough for the rest of my life or at least a long time. It was too bad I had to sell off my collection of Bordeaux but I replaced them with California Cabs. I highly recommend you visit Vivino’s web site. They have some excellent wines at some very attractive prices.

          1. There are many variables in this system that can be adjusted over a wide range. These have to do with time, space, and spectrum and they are interdependent. There is no one right set of adjustments for any recording and so the ability to mold sound into different shapes can be pleasing or displeasing for any one of them. For example, the first recording I played for you has entirely different optimal settings than it did when you heard it. It takes time to explore so many different options to find those you like.

            Today I experimented with the Bach Mass in B minor. I recreated the largest space I ever tried and put myself at a great distance from the source. The first major delay comes at 135 milliseconds. The relative change in RT of high to mid frequencies is 0.8, and the electrical RT (not the same as the acoustic RT) is set at 8 seconds. As Leo Beranek said with a long RT what he calls clarity and what is really articulation is gone with a massed chorus. But what the hell, it’s all in Latin anyway. On solo arias and duets it is still quite clear meaning articulate but not understanding Latin, so what.

            Its a two disc set Sony S2K 66354. The conductor is Giulini. The Choir and Orchestra are Bayerischen Rundfunks.

            The system creates unique acoustic effects that I much prefer over the sounds of other systems. This type of system doesn’t actually reproduce sound but rather reconstructs it. What you hear is mostly not in the recording but the result of a real time hybrid analog/digital computer. That works in conjunction with the 16 satellite speakers that aim their sound at the walls and ceiling. There is no “sweet spot.” Two goals were to make the source of the effect undetectable by ear and the effect itself inescapable anywhere in the room. You may not have realized it but when you were sitting on the sofa there was a speaker almost right behind you on the floor. It’s contribution was so small you shouldn’t have been aware of it.

  6. Paul,

    Part of my job in aerospace is to oversee qualification testing of aircraft parts for the FAA. So when I first read about Ethan Winer and his Null Test I was curious and watched his video and read his articles.

    In short, the test as conducted is flawed for the same reason many of the tests I witnessed were flawed. The environment of the test did not adequately replicate the real world environment.

    In my engineering position I often have to explain why parts tested for 10,000 hours, fail after only 1,000 hours. For most cases the answer is simply that the real world environment is more severe than what was tested.

    For RCA source cables I would like to see a null test conducted that replicates the real world EMI environment of their installations. Cables being tested should be placed in close proximity to speaker cables, power cables, turntable motors, etc to replicate the dense EMI fog in audio cabinets and racks.

    As for Ethan’s Null Test: If you already have decided the desired outcome, setting up a test is much easier.

  7. I good friend of mine in Oakland is a very gifted loudspeaker designer and builder. He’s a lousy businessman, which is why you’ve never heard of him. He makes most of his money sub-letting space in a warehouse where he has his shop. Some years ago, one of his renters was an audio distributor. They had a little show room filled with very esoteric high-end gear, which of course, had speaker wire you could choke a horse with.

    Late one night, he went in there, disconnected the firehose sized speaker cables and hooked in some ancient 24 gauge speaker wire from Radio Shack. He left the firehose stuff there so it looked like it hadn’t been moved. For the next few days, the guys there were just raving about how good their system sounded and they couldn’t imagine what had happened. A short time later, my buddy went back in there late at night and put everything back, never saying anything.

  8. I sent you guys an email a while back asking about my Sprout 100. I explained that I was pushing a pair of Elac UniFi UB5’s and was curious about the AC cord that had originally shipped with your original Sprout when it was crowdfunded. I explained that this was just a living room soundbar replacement and explained that my better resolving speakers and amp were in a different room. But, being a tweaker, I am always looking for any little way to make my system sound better. So I asked if replacing the stock power cord would make a significant difference in the performance of my setup. Your employee, James Herod (he deserves a shout out), replied to my inquiry and basically told me that, although the Sprout/Elac pairing is wonderful (it truly is) it probably wouldn’t benefit much from the more robust power cable you have on offer.

    For snake oil salesmen you have a funny sales strategy. I enjoy reading and listening to your posts and appreciate your candor. Someday I may have enough discretionary income to spring for some of your nicer equipment but I really want you to know how much I appreciate the level of quality that you put into such an affordable piece of gear. I’m super curious to see how the Sprout speaker turns out (although I’m pretty pleased with the Elacs).

    Thanks!

  9. Let’s see. How many people have I pissed off on line about audio equipment. John Curl, Mark Waldrep, Ethan Whiner, Michael Fremer, all of the people on Audio Asylum, and a few other audio sites too. One site went crazy when I said all physicists are stark raving loonies. I’m sticking with that. Then there was that tick tock guy Andrew Benjamin, and remember the guy who stalked me whose girlfriend supposedly conducted an orchestra that made the first multichannel recording and I said she was the world’s worst conductor and as boring as anything I ever heard? I don’t think the guy from Belden who posted on Copper Magazine was happy with my remarks. I wish people who don’t like what I post on this site would just not read what I post. If it makes them angry that just gives me incentive to make them even angrier 🙂 The devil makes me do it. If John Atkinson read my posts about him he’d be pissed off at me too. So far I think Paul and I are still friends. At least I hope we are.

    1. Hi Mark,

      No, nothing you said bothers me. I get to decide what is bothersome to me, not you. Valid question aren’t a bother at all so I consider them to be productive.

      On that end what is a shunt? There is no such thing as any cable will change properties with frequency. We know what we want it to be, though, zero R,L and C.

      Cable should be looked at exactly per your viewpoint. It must look more and more like an ideal shunt. That’s what we’ve done, and that’s what has been explained as to how we did it. Measure the cable, you’ll get the same numbers we do. That’s what customers deserve.

      The argument can be that virtually any audio cable is fine as ANY measured differences are “inaudible”. OK, but Belden sells measurement, even legacy cables could be viewed as measurably unimportant based on that viewpoint. If a signal comes out, you’re done. We design cables for the absolute LIMITS of the system, not the easy pickens. Specs define the worst case limits but for audio, the limits are unreachable.

      You make audio cable measurably better, and that’s the task that needs to be solved. The new 4×4 and 1×4 cables have measurably better attributes compared to an idealized shunt. I show, and explain how that was done, for instance.

      My hope, is that more cable designers will show HOW their products REALLY work. You can argue wheather you can hear true measurement all you want, but better is better, that’s what we do. If you want an idealized shunt, then allow one to be made.

      As far as asking questions go, even five year olds know that asking “why?” over and over reaches the point of ignorance sooner than you think. And, it quickly crosses the line to irrelevance. I need to understand physical wire, not the properties of copper ore, or even go to the origins of the universe if that’s what it takes to construe ignorance. The case can be made, but it is totally invalid to the definition of the problem. We use the wire, we don’t make it.

      I think we see this the same way, except you feel any measurable improvement is inaudible, and I hear the measured improvements against our reference cables are beneficial.

      The question is PRICE. “As an engineer” you should take the best measurement possible towards an idealized shunt. Why not? The why not is at some point we don’t feel we benefit from the improvement. The improvement is still REAL. Everything made hits that price to performance wall, assuming it was made with real measurement to begin with.

      Ask the good questions Mark, but don’t work past their relevance to the project.

    1. Genez,
      have you ever been in a MRT?
      Do you know how noisy, how loud it is?
      With all this noise in mind, how can they produce valuable data?
      Were they using noise cancelling headphones?
      What about EMI/RFI in the tube?
      I might add further questions …

  10. And here we go again with cables and “prove it to me” stuff that you @Paul McGowan so eloquently wrote once a few months ago!

    To me, this is very simple: I try stuff. If they work for me, I am happy. I don’t care if I cannot explain why they work (meaning: sound better than previous cable, amp, you name it). And I don’t care whether I am really hearing improvements, or simply it is a perceived one, like I am hallucinating 🙂 As long as it makes me happy!

    As for those who bash everything they see online as snake oil, my advice is simple: try stuff. And if they don’t work for you, great! you saved yourself some money. Be happy. No need to go online on every single forum / thread you find and accuse people of being snake oil salesmen, or even worse, stupid for being hogwashed

    Most importantly…. relax. This stuff is a hobby. It’s supposed to be fun!

  11. The results of null testing is dependent on the conditions of the test. The source impedance, the load impedance, the frequencies and even the amplitude of the test. Two wires of the same gauge and length made out of the same conductor material will test identically at DC. One might pass RF frequencies, the other might not. If the source impedance was zero and the load impedance was infinite then they’d also all test the same. For those who didn’t take a course in AC electricity or forgot my previous postings a wire is a filter network. It’s most ideal performance is to act as the equivalent of a shunt. Therefore a null test against another cable is stupid. The test should be against a shunt. If it passes that test then it is doing exactly what it is supposed to. Using wire as a filter network to alter sound is just bad engineering. It’s stupid because its results in specific conditions are hard to assess unless you have the data and can do the calculations. It is not adjustable. There are cheaper better more controllable devices to perform this function because that is what they were created for.

    What got Waldrep mad was my comment on his recent posting, “Who Can You Trust.” My answer is that you can’t trust anybody. In his reply he said that means we can’t trust you. He did not publish my response agreeing with him about that.

  12. When it comes to audio I am a believer that there are too many consumer variables to rely on engineering tests for decision making. I read various reviews of audio equipment for information gathering purposes but it is the synergy between components, environmental room acoustics and desired sound requirements that determine my purchasing decision. I keep three different cable looms which I use to mix whenever I am auditioning a major electrical component (preamp, amp, DAC or speaker) to integrate into my system. IMO, cabling is like the condiments used on a sandwich to give us the desired taste. I trust my ears to define when all components are in place for the purchasing decision.

  13. All these arguments over power cords would come to a halt if everyone had the exact same systems that are proven to have excellent transparency, and all agree to try one and the same variable at a time. I am perplexed as to why some hear no differences, but I have as feeling that if I visited their listening room what I saw in their system would explain everything.

    Over the last few days I have been swapping around three different power cords… actually four. Two are two versions of the same cord model, but one uses OHNO copper and the other uses Cardas copper. Definite difference. The other two brands each have their signature sound they contribute to the system.

    If someone heard my system and witnessed to the cable swaps, and heard no difference? Then I would know that their hearing is functioning on a different level. I supplied two links in my earlier post here. They show that certain individuals are gifted with a special sense of hearing that others do not have. It was not about audio tweaks, but about the ability to hear things in music that others can not.

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