Dr. AIX's POSTS — 08 November 2016


Most of you know I’m not a believer in the sonic enhancements attributed to fancy, expensive cables. The simple fact remains that audiophiles love to argue and rant about this issue — usually from their own very subjective point of view.

The other day someone posted a question on a FB group asking whether upgrading the power cables on his system was worth it. Of course, there were immediate comments from believers and non-believers. But what surprised me was a response by a staunch supporter of expensive power cords that the reason the most listeners can’t appreciate the “improved low level details and sonic accuracy” delivered by an upgraded power cord (as well as interconnects — analog and digital — and speaker cables) is because their systems are incapable of “resolving” the new level of fidelity. In simple terms, it’s not that the cables aren’t affecting the sound of your system. It’s that your system isn’t good enough to reproduce the improved fidelity. Therefore you don’t hear any difference.

This is a fairly common response. When challenged with facts, measurements, and physics, cable advocates fall back and blame the equipment — or your ears. The marketing people at the cable companies and the reviewers that continue to push their agenda have done an amazing job. They’ve convinced audio enthusiasts that spending $200 to $3000 on a single IEC power cord will “dramatically” enhance the sound of your system. Instead of spending that money on appropriate room tuning solutions, we’re told to buy adhesive dots to place around the room or invest in a power cord with unobtainium plugs.

So I responded to the challenge. I offered up my own studio, as a place I believe should be more than able to “resolve” the slightest changes caused by a deluxe power cord. After all, my mastering studio sits on its own rubber isolated concrete floor ($25,000), was designed by an award-winning studio architect ($20,000), built by a team of highly trained craftsmen who specialize in studio construction ($139,000), equipped with state-of-the-art analog and digital equipment (Euphonix, Benchmark, Meridian, Bryston, B&W, Oppo – $250,000), wired with cables from Audience and Cardas (provided by the companies but valued at many thousands), and tuned by the acoustics guru Bob Hodas ($700). I’ve been mixing and mastering records in my main studio for over 10 years. Many of you have heard the results. Engineers like my friend Jack Vad of the San Francisco Symphony called it, “among the best sounding rooms” he’d ever heard. So I’m very confident my room can resolve music at the highest level.

Some years ago, a small custom cable designer and builder based in Atlanta offered to send me his best power cord for evaluation — a 6-foot, $3000, blond braided IEC cord (it came in a velvet bag and wooden box). He was very confident that I would experience dramatically better “sonic details and instrument discrimination” when using his power cord on my Benchmark DAC 2 HGC. So I borrowed a second Benchmark DAC 2 and setup a parallel signal path from my digital source to my monitor system. A simple push button on my console switched between the output of one DAC (with the expensive power cord) and the other (equipped with the stock IEC cord that shipped with the unit). It was a blind A|B comparison. The question was simple — do the two sources sound the same or different (the levels were carefully aligned and measured)?

I ran the test with a variety of music sources, genres, labels, and formats. A group of professional audio engineers that work in other studios in the building (including a Grammy award winner) couldn’t detect any difference — and neither could I! I simply let them listen and switch between the DACs — and no one reported hearing even the slightest change. If the designer of the cable notices a “dramatic” difference at his place, I don’t know how he does it. In my “high resolving” studio, no one could hear any fidelity change when using a $3000 power cord vs. the $1.50 one that is supplied by Benchmark (and which they recommend!).

Sure, we all want to have the best possible equipment and to maximize our listening experiences. But if I were to create a list of things that will make the most impact on your sound in descending order, power cords would be very near the bottom (followed only by green magic markers). Great recordings would be near the top followed by the acoustic environment in which you listen to your music and then the speakers. These things make a huge difference.

Don’t ever let someone blame your equipment or your ears when making subjective — and usually ridiculous — claims about accessories and tweaks. Use your ears and brains — and remember the famously discredited video about “audio enhancements” provided by ever more expensive AudioQuest HDMI cables from early in the year. If there is an “unbelievable” change, someone is juicing the results.

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About Author


Mark Waldrep, aka Dr. AIX, has been producing and engineering music for over 40 years. He learned electronics as a teenager from his HAM radio father while learning to play the guitar. Mark received the first doctorate in music composition from UCLA in 1986 for a "binaural" electronic music composition. Other advanced degrees include an MS in computer science, an MFA/MA in music, BM in music and a BA in art. As an engineer and producer, Mark has worked on projects for the Rolling Stones, 311, Tool, KISS, Blink 182, Blues Traveler, Britney Spears, the San Francisco Symphony, The Dover Quartet, Willie Nelson, Paul Williams, The Allman Brothers, Bad Company and many more. Dr. Waldrep has been an innovator when it comes to multimedia and music. He created the first enhanced CDs in the 90s, the first DVD-Videos released in the U.S., the first web-connected DVD, the first DVD-Audio title, the first music Blu-ray disc and the first 3D Music Album. Additionally, he launched the first High Definition Music Download site in 2007 called iTrax.com. A frequency speaker at audio events, author of numerous articles, Dr. Waldrep is currently writing a book on the production and reproduction of high-end music called, "High-End Audio: A Practical Guide to Production and Playback". The book should be completed in the fall of 2013.

(30) Readers Comments

  1. Dr.Waldrep, you myth buster you! Thank You for shinning sunlight on another dark corner.
    I have always marveled at the power of the written word to enslave, or to set free.
    If I ever get the chance, I would like to buy you a beer.

  2. Another brilliant and rational post, thank you Mark. And do keep up the good fight.

  3. How dare you use logic and proper immediate A/B testing techniques! I’m sending you a very expensive box of green markers were the ink has been mixed with 24 carat gold. Darn, I think I probably just gave someone an idea for a new product.

  4. We all got into high end because we wanted better sound quality. However, this is a hobby about having something different. It is about having something only a select few could have. It got nothing to do with high fidelity. Do not expect the believers to agree with you. Doing so would make them lose their unique identity.

  5. I’d be interested in an audio comparison of the best wireless vs cable. Has wireless sound even approached wired at all as fire as fidelity or are we a ways off? What are some resulting measurements of the best wireless headphones or speakers in comparison. Does wireless alter say the sound of a recording you produced?

    • There are wireless systems available that an deliver high-reslution, lossless audio from a transmitter to receiver. Bluetooth doesn’t cut it but WISA standards exist to manage lossless.

  6. I have never fallen for any of the “snake oil” and hype in consumer audio. Accordingly, I recently installed JBL M2 Master Reference monitors with Crown amplification after just a little bit of research into the state of the art in current sound reproduction. Feeding this system with sources selected primarily based upon their provenance results in an immensely satisfying involvement with the music. I believe I have one of the best sounding stereo system available today regardless of cost.

    • Jim, you have the finest speakers I’ve ever heard. I’ve heard the M2 many times and agree that they are the pinnacle of the speaker art.

  7. Great post Mark, and I’ll add only one thing (or maybe two). You said, “If the designer of the cable notices a ‘dramatic’ difference at his place, I don’t know how he does it.” I’m certain his claim is nonsense and driven by a desire to bilk gullible audiophiles. But there is one logical and provable explanation for legitimate perceived sound changes when no change is likely or even possible: In a typical untreated listening room, the frequency response at all frequencies varies enormously over distances as small as a few inches. In your treated room there are likely some small variations, but nothing like what happens in most rooms. This short article shows graphs of this phenomenon and gives a more detailed explanation:


    Okay, one more point: Human hearing is notoriously unreliable. You’d think that anyone who considers themselves an audio professional would understand the limits of their own hearing. But many do not, even some professional mixing and mastering engineers. My article above offers a solid explanation for why the sound really can change, but not because of replacing wires or adding expensive isolation pads etc. But the larger issue is people believe they hear a change even when nothing changed and they didn’t move this head either. The longer the gap between hearing A and B, the less reliable the comparison will be. This is established science.

  8. The Benchmark is a good dac, and I have found the USB interface to be first rate, I own one. But you can’t test cables on one piece of equipment and say that cables and power cords don’t have an effect on all equipment. And while Oppo is a real value for it’s cost, it is not state of the art, it does not compare with much more expensive players. Your testing is flawed anyway, going through your console. That console could be imprinting its own sound on everything that goes through it. Actually, none of your components would be considered state of the art. The B&Ws, the Brystons are how many generations back are they from their much improved current models.

    I’m not advocating for expensive power cords, I do agree that power cords should be one of the last things you do. Speaker cables and ICs can change the sound, based on electronic principles. Different capacitance, and the other technical aspects of the cables. That stuff is measurable. Rejection of noise, many cables have no shielding.

    I have wanted to ask you, do believe that disc transports make a difference? Do you think the digital output on a $100 universal player will deliver the same results as a purpose built high end transport? What about using a computer vs a purpose built player like the Aurenders, outputting to a dac?

    Since I upgraded my preamp and dac, I hear more details in CDs that I have owned for years. That means that those components are more resolving than the old ones. It does take a highly resolving system to hear small details. I don’t see that as a controversial statement. I think people need to trust their own ears, in their own systems. If cables don’t improve the sound, return them, but put a couple hundred hours on them, before making comparisons. Burn in of cables may be controversial, but not components or speakers. Please tell me you believe in burn in, that speakers need time to flex their surrounds, capacitors need time for their dielectric to form?

    I look forward to your answers on transports, music players, and break in?

    • Jeff, you and I aren’t going to agree on a number of issues. First, let’s talk about the evaluation that I did in my studio. Taking the digital outputs of an OPPO machine to two identical and carefully aligned Benchmark DAC 2 HGC units and monitoring them via my console is a valid test of the power cord manufacturer’s claim of “dramatic” sonic improvements. The only difference between the two signals was the expensive cable vs. the cheap IEC power cord. The “sound” of any other component would be the same for both A and B signals. The oppo is state-of-the-art when it comes to delivering the S/P DIF digital data streams to the DACs. The Benchmark DACs reclock the data and convert to analog. An expensive transport would make no difference unless you used the conversion local to that machine. You might want to believe that the digital data from a Meridian, Burmester, or Goldmund transport would make those bits “better” somehow, but they simply don’t. If you want to challenge whether my listening room offers sufficient “resolving” power, I would like to hear about your setup. The equipment in my room remains fully capable of very high fidelity.

      You hear more details in your CDs when using an upgraded DAC and preamp, I believe those elements could contribute to a better listening experience. We all strive for achieving the best fidelity possible but one person’s “better resolving” system might be someone another person’s nightmare. I know people that swear by analog tape. Are tape decks capable providing “better resolution”, obviously not. They reproduce a sonic signature that many people like.

      As far as cable burn or component burn-in periods? That’s a myth just like expensive power cords. The current following through a wire or circuit board doesn’t improve over time. However, speakers do benefit from having been played for extended periods.

      • Mark, I apologize if you thought I was insulting your listening room, I am sure it is first rate. And compared to some other studios your equipment is very good.
        By today’s standards it is not state of the art. The newer Bryston amps are supposed to be quite a bit better. As to your speakers, I last heard a pair of your generation probably 15 years ago, with Threshold amps. They were very good, the drivers and cabinets of the current models are superior.
        As to hearing more detail, I think it has to do with my preamp being quieter, the last preamp had some tube hiss, this one is dead silent. My system is not not bright sounding or fatiguing in any way. And I wasn’t trying to claim my system is better than yours. My Oppo is a 83se ,a few generations old. We have the same dac, although I am currently using a friend’s Lindemann 825 as a dac. The internal disc drive has been back to Germany twice, and it still doesn’t consistently read discs. Transport is a PS Audio PerfectWave Transport. The preamp is a Conrad Johnson CT5. You have a better amp, mine is a Legacy High Current made by Coda. If the budget allowed I would most likely buy a new higher end Coda amp or amps. The speakers are of similar generation and value a pair of 1997 Legacy FOCUS. The preamp, transport, dac, and Magnum Dynalab Etude Tuner are plugged into a PS Audio P300 power regenerater.
        If you have any interest in cables, room treatments, and my analog front end, my systems are posted at the Audio Asylum under Inmate Systems.

        The reason I asked about transports, years ago I had a Cal Delta, a very nice transport, but it had problems reading a few discs, one in particular a XRCD of “Mulligan Meets Monk” it would stutter. Well one of my local dealers, the same one that until recently sold B&W, had a used PS Audio Lambda Transport. He let me take it home, all I was looking for was that it could play the discs I was having problems with, no expectations. The improvement in sound, particularly better bass was not something you had to struggle to hear. So when you tell me that transports don’t matter or the cables between them, you lose me. I believe everything matters in a high end system. Isolation, clean power, eliminating noise that rides along on a USB cable. It all adds up to getting the most out of the system you have.
        I am not surprised you heard no differences with the Benchmark Dac2. I am saying that cables and cords do make a difference in some systems with some components. And not every difference is an improvement. Maybe you should remove those Audience speaker cables and run some lamp cord. It just might surprise you. Bypass the board, use the Dac2 as a preamp, one of your fine recordings as the source, do it in stereo and see if the soundstage changes, listen to the cymbals, the bass, the details. Exactly the same? Send me the Audience cables, I’ll buy you five hundred feet of lamp cord. You can include a 10ft pair with the first 25 books you send out;-)

        I don’t disagree with everything you write, I agree with you on provenance and that we need better recordings. Unfortunately a lot of the music I love was recorded in analog, and the best I can hope for is a good digital transfer from a first or second generation tape at 24/96.

        • Jeff, no need to apologize. I understood your points and agree that there are components that would elevate my system (I’m all about the JBL M2 Studio Monitors…amazing!). But the sound produced in my room is first rate and I’m confident eclipses just about any consumer system. But in reality, none of that matters. The central issue is whether a different power cord ($3000 vs $1.50) can and does alter the sound through the same signal path. My evaluation showed that in this circumstance it didn’t. Take that as wide or as narrow as you want. Given that the provider of the cable assured me that I would hear “dramatic” differences, I feel comfortable in doubting his claim in this instance and in others as well.

          I’ll hang on to the Audience cables…John was kind enough to provide it and my rooms sounds great. Would 12 or 14 gauge zip cord sound just as good…I haven’t done that comparison but I suspect it would.

        • How about this Jeff: I have $1K that says, in your system, you can’t tell the difference between a boutique PC and one I construct, when properly bias controlled.

          If you can hit 14/15 coin flips you’re golden. If you can’t you pay for my airfare, hotel, rental car.

          I think a good litmus before any testing is you go for a 5 round 320Kbps mp3 vs 24/192 PCM track and hit it 100%.

  9. My father is a Ph.D APS member who did signal processing research for the US military for 38 years. He’s an expert in electrical conductivity. He says that if the guys selling boutique power cable had to stand up to formal peer review, they’d get massacred. They are con artists who don’t know physics.

    • Thanks for sharing your father’s experience. He’s right but the cable mafia continues to push their mythical products and convince compliant reviewers to go along.

  10. Unless one believes supernatural forces are at work, you cannot hear a “difference” unless it is present in the electrical signal being fed to a loudspeaker.

    Accordingly, we can set up two identical amplifiers and invert the phase to one of them. Feed the pair with the signal source of your choice. If the outputs electrically null (i.e. cancel out), then the two signal paths are identical.

    Next swap power cables, interconnects, etc. for one of them. If the null remains after a substitution, you have proven that the change had no effect whatsoever. So save your money…

    Skeptical audio hobbyists can recreate the null test at home using the two channels of a stereo amplifier. Golden ears, expensive listening rooms, high end loudspeakers not needed…

  11. Another great blog post Mark.
    Thanks for the time you take to shed light on the snake-oil peddlers of our industry!
    So much of today’s high end audio marketing is a disgrace. 🙁

  12. I have followed the cable controversy for years. Any time circuits are tested, the test instruments are immediately called into question. Building inertial guidance platforms for fighter planes at Litton Industries, required that we use calibrated voltmeters, i.e., ones that were hand carried to NBS in Colorado, calibrated, and returned to the lab in Salt Lake City. It is no different in evaluating sound reproduction. The test instrument is our ears but I’ve never heard of any audiophile reporting on his hearing test even though high frequency drop-off with age is a known condition. So, what you hear is not what I hear. In an A-B test, I don’t change ears but if your subject device caused a change, say above, 10kHz, I would not be able to detect it. So hearing audio is not an objective testing method.

    The obvious solution is to not depend upon our ears, but upon devices designed to detect even the slightest variation in an electronic signal. Oscilloscopes can usually be configured to do this adequately. Why is it that cable hawkers don’t use instrumentation to show the differences in cables? When they do, I’ll take a second look.

    • Good comments Robert. You’re absolutely right that our hearing is one component in the chain and is subject to age and interpretation. I tend toward null testing and a scientific approach when checking things.

  13. Sounds like you set up a very fair test of that $3K power cord – you changed only one variable, the cord.

    Given you have great recordings, components, and the inclination, it would be very interestiing if you ran similar tests for speaker, interconnect, and USB cables.

    I agree that great recordings are the most important piece of the puzzle. Even a great sound system can’t turn a mediocre recording into a great one; but a mediocre recording can make a great sound system less than great. There’s a reason they don’t run super race cars on regular fuel.

    • I actually have done the same sort of comparison and the null test on a variety of cables including interconnects and digital cables (USB, S/P DIF etc). I haven’t done it for speaker cables. The results consistently show that cables DO NOT alter the sound of the audio signal passing within them. It’s long past time for the snake oil vendors, reviewers, “experts”, and subjectivists to come clean and stop perpetuating the myths that make them all money. The world of professional audio exists without all of this nonsense, why can’t audio consumers get the message?

  14. As an electrical project engineer, construction project manager, director of engineering design and construction of mission critical facilities, and the chief electrical engineer of two large world class leading edge telecommunications laboratories (one presently) I’ve successfully completed projects from start to finish on many leading edge laboratories with state of the art scientific equipment and spent millions of dollars of other people’s money on all manner of wire in the process. High quality products from the largest and most respected mainstream wire manufacturers have never created a problem, not even once in nearly 50 years. Why are your junky little hi fi sets an exception? If I specified the kinds of products on my job audiophiles buy I’d be fired and with good cause.

    The correct way to test whether or not wire has an effect on performance is not to compare wire A against Wire B but to compare wire A against a shunt. These test devices are easy to build for anyone with any tech savvy.

    Electrical engineers and manufacturers probably know more about what there is to know about wire than any other electrical component. The Telegrapher’s equation models wire. Thevenin’s theorem models the network and shows how changes in wire parameters in the Telegrapher’s equation affects performance for a specific case.

    The mainstream wire industry has created products to address every conceivable engineering need and problem that are cost effective and high quality. Can changing wire change performance of a sound system? Under certain circumstances yes, that is a conclusion of crunching the numbers. Should it? Compared to a shunt it should not. It is not a good control device. It is usually bought on trial and error, expensive, not adjustable, and most of the time not predictable as a distributed parameter filter network which is exactly what it is. Throw your money away, I don’t care. It doesn’t affect me. But if you want the facts from someone who knows, here they are. If you have a problem you think wire could solve and you are a tyro audiophile, you’d do far better to look for the cause and cure of the problem elsewhere.

    • What are some examples of high resolution equipment? A 90,000 power electron microscope. The Hubbell space telescope. A machine that photographs individual atoms (yes such a thing exists.) A liquid chromatography mass spectrometer. An atomic clock that loses no more than one second in 100,000,000 years. A machine that sequences the DNA of a cell and gets it right every time. What is an example of something that is not high resolution? An audio recording playback system with a frequency response to 40, 50, 100 kHz. One big difference between the first category and the second is that the second category requires special wires to work well, the first one does not. At least not the ones I’ve ever seen and I’ve seen more than a few of those. Even installed some of them.

      • High resolution in audio is not related to any of the examples you mentioned just as Ultra High Definition or 4K video doesn’t. High-Res only applies as an absolute measure when appropriately defined — and that’s where I’ve had such difficulty with the CEA board and others. The recordings I have produced are high-resolution according to my own definition. They meet or exceed the capabilities of our human hearing systems. The DEG, NARAS, CEA, and labels pull the definition down to anything “better than a CD”. The magnitude of the numbers doesn’t automatically make something high resolution.

        • re·solv·ing pow·er

          noun: the ability of an optical instrument or type of film to separate or distinguish small or closely adjacent images. the ability of an electronic device to produce images that can be distinguished.

          In the scientific sense this relates to the ability to distinguish small incremental differences. The difference between one star and another in a distant galaxy. The distinction between one atom and another in a machine that photographs atoms. The ability to determine the sugar sequence in a strand of DNA. The ability to distinguish between two molecules that are almost identical.

          Resolution in hearing means the ability to determine small differences in pitch and loudness and that is about all. Existing high quality sound recordings and reproduction systems can do this within the normal range of human hearing and certainly within the range of musical sounds. For RBCD standards incremental pitch accuracy is at least 10% better and loudness incremental accuracy is at least 10 times greater than people who claim the best hearing acuity. Does a sound system that can produce the sound of a jet aircraft taking off or ultrasonic frequencies add to resolution? No. The term high definition audio has no scientific meaning, it is strictly a marketing term. If you want to call it ultra wide band or ultra dynamic range that’s another matter entirely. There are aspects to sound that are not included in any of the performance parameters or descriptions such as resolution of angular arrival of sounds in both the horizontal axis and vertical axis. Compared to live sound all but a few experimental sound systems perform atrociously by this measure. Their distortion in this respect is truly lamentable. This aspect of sound not only controls the perception of direction of the source of sound but is inseparably bound up in the perception of acoustic space. I’ve experimented with it for over 40 years and I’m done with it.

          • I understand the usual definition that is applied to resolution and how it differs from the rigid definition you described — and I agree that it is being misused.. But it has been appropriated by others in other areas and applied to related concepts — accurate or not. I fought very hard with the CEA board about their use and misuse of the term. High resolution audio moves technical specifications (frequency and dynamic range) to places that may eclipse the normal human range of hearing but how it’s easy to do, costs nothing more than standard resolution, and provides potential improvements in audio fidelity. The dynamic range of RBCD doesn’t meet the abilities of human hearing so why accept a limited format?

          • Wouldn’t 21 bit 44.1 be really the limit if we are talking the thermal noise floor of circuitry?

          • We want enough bits and samples to exceed the ability of human hearing. Beyond that, it’s all over kill (like 384/32-bits). The reality is that the masters coming from the artists don’t exceed the specs of a CD…so the practical side of the whole high-res thing is moot.

  15. If changing a power cable affects the sound of the equipment, go tell the equipment manufacturer to design his power supply properly…
    Ever since the audio industry got exemption from the European EMC standards in the 1990s, we’ve been left with excuses for poor design in a world with ever increasing interference.

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