Dr. AIX's POSTS — 19 February 2016

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When it rains it pours. I’m sure many of you are tired of hearing me talk about cables but it’s a topic that just keeps on giving. The other day I clicked over to an article on Positive Feedback written by Dave Clark that tries to explain why USB digital cables can make a difference. Dave apparently asked a few of his cable designer friends to help clear up any confusion about a few misplaced ones and zeros. You can read the piece for yourself by clicking here.

I could go through every paragraph and comment on the points made by the writers but I think I can sum up their approach in a few paragraphs.

One common focus seems to be on “data errors that cause audible losses” because of the lack of error correction, noise in the cable, or a loss of waveform fidelity. It’s true that music data can suffer from transmission problems under unusual circumstances, but the reality is that a 1-meter length of good quality USB cable can successfully deliver the ones and zeros virtually 100% of the time. Contrary to the repeated claims made by the designers, there is only a problem if the data is severely corrupted. And it would have to be corrupted a whole lot to damage the fidelity of the digital signals traveling 1 meter. In the real world, all of the data bits are successfully delivered from the source to the destination…in spite of any background noise or compromised data waveforms. All we have to do is get the data in tact, and then we can rebuild the analog waveform.

The second aspect of USB infallibility are the timing errors that are the result of “reflections and clock inaccuracies” inside the cable. The reality is that jitter is not an issue in a well-designed DAC because the incoming (jitter damaged) clock is not used…AT ALL. The electrical engineers that design and build high end DAC know that jitter can be a problem and they go to great lengths to use their own clocks inside their devices…clocks that are highly accurate and virtually jitter free. So the cable designers could well ignore any potential clocking errors in their expensive cables.

The final point made by the cable designers is the power lead that is part of the USB connection. The claim is made that the “transmission of power from the host to unpowered USB devices. The 5V power legs within a USB cable can also cause problems with the integrity of the D+ and D- signals if not properly isolated”. But what if the power is properly isolated as is the case in high end systems? Why bother talking about the potential problems when in the real world of high end audio they rarely if ever exist?

The gist of the articles is that certain bad things CAN happen to a digital stream. And those bad things have the potential to modify the audio moving from a source to a destination. But in the real world folks, those potential problems don’t happen or they happen very, very rarely. So would you accept the cost and logistics of building a 20-foot high sand bag barrier around your house in the Mojave Desert to protect your property from the once in a 100-year flood?

Think about the title of the article…”Why USB Cables CAN Make a Difference”. Then consider these two things: who contributed to Dave’s article and what would motivate them to overstate the “problems” with USB digital cables.

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About Author

Dr. AIX

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.

(53) Readers Comments

  1. Hi Mark. Just two comments today: Dave Clark has ears that work, claims aside. Second, the usb connection is noisy, and I have a device that shuts it up, the ‘wyrd’ from Schitt. W/out, turn level all the way up w/ computer and dac selected, and put your ear to the speaker. Not typical noise, but audible grunge is present. Connect the device containing ultra-low noise voltage regulators in between usb out on computer and associated gear; system is now silent. To think that any signal path is impervious opens up exactly this can of worms.

    • Hi Craig…no argument with Dave Clark. He’s a member of the same audiophile group here in SoCal…and certainly has a long history in the field. If you believe that a “noisy” USB connection is contributing to audible noise in your speaker outputs then something else is wrong with your setup. When I turn up my Benchmark DAC and listen using my $5 USB cable, I don’t get any noise compared to the the $300 USB cable I was given. I can’t say that I’ve auditioned the Wyrd unit but I also don’t think I have to. A properly spec’d USB cable from source to destination traveling 1-meter isn’t impacted by noise. Therefore no regeneration or cleaning is necessary or beneficial…except to the pockets of the vendors selling expensive cables and nonsense accessories.

      • It’s not an original idea of mine that the usb connection is noisy. I have done a with and without here in my shop; thru an Aurender server and Musical Fidelity MX-DAC, the sonic background was noticeably improved with the Schitt unit in line, and the sound was more spacious.

        • Craig, you’re welcome to hear and believe what you like…the science and technology just doesn’t support your observations.

          • If we assume that we know all there is to know, progress ceases to occur. I’m not taking a pro or con position re:cables or audiophile accessories.

            Here is my question, please give me a sensible answer:

            The “wire thing” has been going on for decades, and tens of thousands of folks have participated.

            Do you take all of these folks (who have generally above average intelligence) for mindless chumps under some kind of audio mind control? Do you think that people will actually spend money over and over for something that does nothing? Do you think that a dealer with a hard-earned good reputation would willingly sell someone a completely bogus product? Last of all, if I spent money on any kind of supposed audio upgrade and it made for no improvement, I would get my money back. This idea that folks pat themselves on the back for making mindless mistakes over and over is groundless. ” Something’s going on but you don’t know what it is…” Bob Dylan

          • Craig, I agree that we don’t know everything about audio but we do know a lot. And there are things that have been firmly established in this industry thanks to researchers at universities, private research facilities, and yes, at cable companies. There are fundamental physical and electrical properties that are not subject to the whims and exaggerations made by cable makers, dealers, and their supporters.

            I’m limiting my discussion to digital interconnects for now…this one is well known and incontestable.

            Do you take all of these folks (who have generally above average intelligence) for mindless chumps under some kind of audio mind control?

            It’s not mind control but I do suspect that peer pressure, advertising, reviews, testimonials, and other factors (like having too much money) have made people invest in things that do nothing. The high end cable market is more about visual appeal, the “jewelry” effect, than sonics. They may think they hear differences but any perceived fidelity change is the result of something else. People do some amazingly stupid things.

            Do you think that people will actually spend money over and over for something that does nothing?

            Very definitely yes. Why else would people like Geoff Kaitt of Machina Dynamics continue to sell admitted “snake oil” to audiophiles?

            Do you think that a dealer with a hard-earned good reputation would willingly sell someone a completely bogus product?

            Absolutely! The margins on digital cables can be seen as a great opportunity to make up for discounts on the gear. It happens all the time. Dealers are no different than other business people, they want to make a profit on the things they sell. I don’t think that all dealers are crooks, they have convinced themselves that they’re offering the best option to their customers.

            Last of all, if I spent money on any kind of supposed audio upgrade and it made for no improvement, I would get my money back.

            So would I…but I believe that many people have been told that digital cables will be “faster” or “add an extra octave” to the output and want to trust its true. I listened to the REGEN and it did nothing to the sound in my studio in spite of others claiming to have heard more “depth” in the sound. There was no change.

            Let me ask you a question. When you read a review for a high end cable, do you find them credible? What do you think when you read review phrases like (this for a single meter USB cable):

            “The improvement rendered by the new cables was not subtle or minor or difficult to detect. On the contrary, inserting them proved to be one of the most flabbergasting experiences I have ever had in the high end. The Reference line did not improve the sound; it took it into another realm. As good as the Vivaldi is—and it is superb—there can be doubt that ancillary equipment such as the digital cables employed on it not only can but do have a profound effect upon its reproduction of music.”

            If the same data comes from the expensive cable as from a cheap cable, what could possibly change the fidelity? Forget jitter, noise, and data errors…these are things we know.

    • OMG you’re using your ears? Really?

    • Hi Craig,
      The noise you are experiencing is real, and most USB DACs suffer from it. However, a USB cable no matter how expensive does not help with that situation. It does not clean up power noise. You need a device like Schiit Wyrd or HiFimeDIY USB Isolator to get rid of that noise.

      • Most high end DAC connected to digital sources via USB do no suffer from audible noise on the analog outputs! And you don’t need a Schitt Wyrd or Regen device to “clean” it up…any noise coming from you DAC is the result of other grounding or interference.

  2. I cannot agree with you more Dr AIX. I have some USB cables that MIGHT give off some bad data but I find it highly unlikely.

  3. I just took a look at that article. And that guy IMNSHO is an idiot. Blithering too. I listen to my LH Labs Pulse DAC and I never have hear so much as an error. 1+0 are not corruptible in the normal world. As you stated in your article, it would have to be some very extreme conditions to corrupt a data point.

  4. Ah, now I have a better insight to whats going down.
    I was there yesterday and made a reply to poster Douglas Henning, that post stands there now. Earlier tonight I received a email that Douglas had replied to me, so I went there and read his reply which was fine. I then responded with a very polite post pointing him and the others to other opinions on the subject, John Siau’s post here, Gene DelaSala’s recent Audioholics video
    https://youtu.be/BgDB86tkth8
    and made a few comments on the constant railing of subjective’s against any blind testing.
    The post went up but within five minutes it disappeared. Thinking it was possible I made a error in the post, I typed up a similar response again and posted. Again after being up about five minutes it disappeared.
    There was nothing in either post to justify their deletions except for the fact that whoever had their fingers on
    the delete button didn’t want any opposing opinions from EE professionals to be aired.
    After the second deletion I did made a third post telling the moderator what I thought of his unsupportable censorship on the site and tried to explain to him in the USA we have a thing known as freedom of speech, the free press, etc. Again in less than five minutes it too was gone. DUH, LOL
    It does just amaze me how many in the subjective community will go to almost any extent to discredit, make fun of, and silence-sensor out any voicing of a objective position.
    As I said in my last deleted post, PF should be ASHAMED of their unethical posting practices.

    • Sal, the guys running high-end cable businesses and the publication (online or physical) have no interest in changing the nature of their respective businesses. They depend on each other. Hearing contradictory positions or even seeking out independent third parties is not going to happen.

      • Yes I knew that, but after a guy puts up a article supporting audible differences in USB cable by stacking the deck with a bunch of long custom written letters written by the manufactures. I had to try and say something. I also know PF to be a safe-haven for the subjective community but as in the AQ video there are some moves so outrageous you can’t ignore.
        For some reason as of early this afternoon one of my posts was drug out of Pluto and put back up, probably because I was going public with the shenanigans. Its a two line post but at least does include the link to Gene Delasala’s latest video on cables.
        There are three more that were rejected but I have copies of them all and they still exist in my disqus account. They contain very respectfully just more of the same posted here. But if anyone would like to see them just PM me at
        Computer Audiophile, whatsbest, head-fi, s hoffmans, many others. Sal1950 everywhere.
        I have nothing to hide.

        • Opps, I spoke too soon, The changed their minds and deleted the post for a second time in 24 hours.
          Now I’m not so nice, Cowards

    • Hey Sal, Dave Clark just deleted my comment on the same article. I pointed out that Andreas Koch, the designer of Playback Designs DACS, is listed on their site as a Senior Technical Editor. And on the Playback Designs web site Koch basically states that all USB cables will sound identical, similar to what the Benchmark Audio folks believe, and suggested he post a followup article on the thoughts of DAC designers on high end USB cables.

      But you will never see my posting.

      So keep at it Mark, it’s great that bloggers like you and Archimago are exposing the outright fraud in areas of the audiophile world such as exotic digital cables, along with the advertising-supported audio publication world that is paid to perpetuate their myths.

      • Here’s the replies I got for nicely complaining about the censorship. Bottom line is he will accept a two line bits is bits sentence from a rank amateur (me), but nothing from any other EE like John Siau or Gene DelaSala or links to any info on the AQ HDMI hoax, neither here nor at whatsbest or any where else. A shameful setup job right up there with AQ HDMI.
        I have edited out presonal email address

        Welcome to repost minus the video.

        Sent from my iPhone

        On Feb 20, 2016, at 6:22 PM, Sal wrote:

        “So just say… “It’s a digital stream signal, 1s and 0s. If your DAC removes jitter by replacing the sources clock with a new, highly accurate clock there can be no audible changes from the cable” as you did below.”

        That’s exactly what I posted along with the link to Audioholics video below it.
        So why did you then delete it, TWICE
        You delete it twice and then say that was OK, I don’t get it.

        On Sat, Feb 20, 2016 at 7:15 PM, Dave Clark wrote:
        Sal, the site is not there to debate audio topics – take that to a message board. We are open to different opinions and disagreements – for example, you do not see how USB cables matter and don’t hear a difference but others do – and for sure and want and encourage people to participate, but in our opinion you went too far with how you said what you said. You don’t agree, fine.

        So just say… “It’s a digital stream signal, 1s and 0s. If your DAC removes jitter by replacing the sources clock with a new, highly accurate clock there can be no audible changes from the cable” as you did below.

        Thanks,
        Dave Clark
        Editor, Positive Feedback

        —–Original Message—–
        From: Sal ]
        Sent: Saturday, February 20, 2016 3:06 PM
        To: dave clark
        Subject: USB Cable

        Full Name: Sal

        Email:

        Phone:

        That was a lame excuse and untrue. My posts were polite and respectful.
        What was wrong with these two lines along with a link to the video done by EE Gene DelaSala?

        It’s a digital stream signal, 1s and 0s. If your DAC removes jitter by replacing the sources clock with a new, highly accurate clock there can be no audible changes from the cable.

        I have all the original posts and am releasing them to anyone who asks, word is getting out. You’re just scared to allow for an open, honest debate.

        • Sal, other sites and editors are free to police their sites as they see fit. PF is a site that many regard as good source of information about audio. However, they are a part of the closed community of commercial sites that depend on maintaining good relations with their advertisers. And BTW Gene is not an EE as far as I know.

  5. Yes, when a boutique USB cable designer starts talking about errors, just filter him out. He is lying to you.

    I ran test tracks of two hours length over cheap USB, over hubs, over USB extenders, while having other devices access USB, loaded as heavily as possible and while having the computer do CPU intensive tasks. At 96 khz and 192 khz over dozens of hours of such runs guess how many data errors were encountered? Exactly, and precisely and conclusively ……ZERO, NADA, NONE, as in not one. Many trillions of bits and NOT ONE SINGLE ERROR. Error with the any decent USB cable, as in usually less than $10 cable causes errors so infrequently as to be a TOTAL ABSOLUTE NON ISSUE!!!!!!

    I wish interviewers had the balls to just stop such statements mid-sentence and call BS.

    The rest of their conjecture about dirty power has some exceptionally remote chance in hell of being true. Basically it is about as trustworthy as their talk about errors in transmission. As in a single chance in some large number of trillions.

    • Thanks Dennis for sharing your experience. I’ve done the same thing…a quality digital USB cable doesn’t have to cost more than $10. Imagine my incredulity when I read the following review of a 1-mter USB cable, “I auditioned the Oyaide d+ Class A USB cable briefly each day for a week, tracking the sonic changes as it warmed up. Some days it sounded shrill, other days dull. By the fourth day, it sounded quite coherent, and encouragingly similar in many respects to the reference, but still a little sweet and euphonic in the upper octaves.”

      Digital cables don’t “warm up” and they don’t sound different on different days!

  6. First of all a good day to everyone.
    I have been following this blog for quite some time now, and in particular I have been reading all the articles about the “cable gate”.
    I have always wondered about the crazy prices reached by “audiophile cable” some “worth” 7000$/m, but I am still confuse about the technical specifications a good cable (usb audio cable to connect computer to DAC) should have and what can be a reasonable price (per meter) for that cable.
    Regard.
    PS: I apologies for my english, as you all well know by now, it is not my mother tongue.

    • Alessio, you don’t really want to read through the pages and pages of specifications regarding the USB format. Despite the subjectivists claiming otherwise, a 1-meter digital cable of reasonable quality that meets the USB spec will not affect the fidelity of your system. Spend no more than $15 on a nice basic cable.

  7. On the topic of cables, it’s easy to misdirect an audience by referring to “issues” that are difficult to explain, difficult to comprehend, or just difficult to quantify objectively. When this is done in a manner that makes it look official of authoritative, the result is a viral like acceptance as fact.

    I too am a computer scientist and audiophile and I prefer to rely on science and not innuendo to support a statement or argument.

    With the introduction of digital storage formats for audio, for reproduction of a recorded audio signal there are the elements in the digital domain, the elements in the analog domain, and the digital over analog domains. Many times these all get lumped together and the boundaries between them not respected.

    When it comes to digital interconnects, I have been intrigued by the aspect of cable selection and the impact of a cable on sound quality, or more specifically if there is any impact at all. It appears to me that depending on the cable, certain design deficiencies begin to be exposed in the devices the cables are connecting. The fact that the connected devices may be truly at fault is very heavily overlooked.

    For USB, which is a digital transport, there are specifications that when met by the manufacturer, and used in accordance to the specification, then that cable shall provide the reliable transport of the “bits” at the data rate the cable is designed for.

    There’s lot’s to discuss here, but let’s start with the two most obvious: Jitter and Noise.

    • Jitter: As you point out, a decent DAC component should be re-clocking the data stream through a FIFO to eliminate jitter, either sourced at the sending device and/or manifesting in the cable. If the DAC stage isn’t addressing that properly, no cable is going to fix this problem.

    • Noise, specifically, injected noise from the sender: This comes up as a result of using a general purpose computer system in an audiophilic manner. General purpose computers have been notorious sources of electronic noise, as EMI and as unclean/noisy power rails.

    There is a requirement for a cable to address noise immunity for EMI, but if you are in a high EMI environment, then that EMI may in fact be affecting more than just the cables.

    With music, and more specifically with hi-res music, as opposed to reusing or adapting old standards, there needs to be new standards and certifying specifications for the evolution of the devices and methods being used and the respective interconnects required. There needs to be a broader understanding that general purpose computers and USB were not designed for digital audio transmission. They are general purpose, and USB has been a convenience, where convenience shall outweigh quality.

    The bottom line here is that cables are an easy “monster” to try to slay, when it fact there are other more hideous monsters hiding under the bed that no one is paying attention to.

    • Very well stated…thanks Darren.

    • Thanks Norma…this just days after I downloaded the same sort of advertorial nonsense from a domestic audiophile publication. I’ve been through both of them and read nothing but glowing reviews, interview responses that contain nonsense answers, and plenty of “glossy” ads. Does anyone think that a writer would dare challenge the spew coming from the cable designers? More to follow…

      • This Guide is brought to you by our Premier Sponsors:

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        • These cable and equipment guides wouldn’t exist without the generous support of the sponsors…it’s about money over truth.

  8. I have observed differences in sound quality between USB cables.
    No one argues with a DAC manufactures’ decision on power supply, board layout,
    etc. And yet, the digital source is electrically connected to the DAC via USB.
    Two power supplies, noise levels, and even grounds. I had two Brix PC’s both running
    J River. One was a Celeron and USB2 the other an I3 USB 3 and they difference
    was obvious. However, the same bits.

    The iFi USD3.0 has significantly improved the sound in my system. Signal conditioning may be
    the answer and may provide an improvement where expensive cables are really
    fiddling around but not fixing the problem. So this may be more about a particular environment than cryo-freezing a cable.

    The BenchMark DAC2 manual dedicates over 2 pages to discuss the “UltraLock2™ Clock System” and the importance in accurate reproduction. I’d love to hear this product someday. Given the existence of interface jitter, ground loops, poor source power, It may be that higher quality cables can change the behavior of some DACs.

    For the record, I use an IFI 3.0 USB with mono-price USB cable and Kimber 1 meter USB. I bought the Kimber a while back. I have no intension of purchasing uber-priced cable.
    My observation that the cables and the IFI make a difference suggests that quality USB audio is not guaranteed because it is digital.

    – Rich

    • Rich, if you experienced different fidelity between two USB cables that meet the USB specification then something else is amiss in your system.

  9. It should be noted that data errors in a digital transmission do not cause slight changes in timbre or whatever. They cause terrible pops and screeches that nobody could miss.

    It’s also amusing that the various explanations offered seem to be in part contradictory. That’s reason enough for me to believe they’re simply making things up.

    • They are making things up…and seem to do so in a collective way. Have you noticed that they all chime in on the small factors? Jitter comes up a lot even though no high end DAC uses the clock supplied through the cable. Small digital errors in a cable won’t necessarily cause a major dropout or pop, it takes a lot of missed information to do that.

      • Thanks for another no-nonsense post, Mark.

        As Mans said, digital errors, should they occur will be *obvious and ugly*. For those who want to hear what this sounds like using a cheap USB1.1 cable pretending to be USB2:
        http://archimago.blogspot.ca/2014/01/demo-measurements-what-does-bad-usb-or.html

        Jitter is a nonissue these days with asynchronous USB. Even with poor components, it was never something a 1m cable could affect or solve in any event!

        As for noise this can be a little more complex since USB connections are typically not galvanically isolated. Data and power lines could transmit noise. Ground loops and computer noise could be transmitted to the audio system but as you indicate, a good DAC should not be affected by this. Last year I made a post about this for folks to consider since I was picking up some noise through my pre-amp’s analogue inputs (I have a reasonably complex setup with preamp, receiver, HTPC, DAC, Transporter streamer, monoblock amps all hooked up together):
        http://archimago.blogspot.ca/2015/05/measurements-corning-usb-3-optical.html

        I was able to ameliorate a significant portion of this with the Corning USB3 *optical* cable although it’s not complete isolation.

        Thankfully these noise issues I believe are not common with most setups and it would be ridiculous to think that an audiophile $100-$1000+ cable would help unless there was some real science in there providing true isolation!

      • Even a single flipped bit is clearly audible if it’s one of the more significant ones. There is no reason for cable-induced data corruption to be limited to the least significant bits of audio samples.

        • True…

  10. A few months ago, scientists were thrilled at receiving sharp color images of the surface of Pluto (once called a planet but no longer and smaller than Russia) that were transmitted from nearly 4 billion miles away. That transmission survived the ionized solar wind, cosmic rays, the asteroid belt, and lots of other stuff out there, space being not entirely empty. Yet in the audio industry it seems engineers struggle to get a narrow band audio signal three feet down a wire from a CD transport or computer to a DAC without messing it up. What does that tell you about their capabilities as engineers? There are other choices. Direct radio link is one, fiber optic is another (no I’m not talking about Toslink which is ersatz plastic masquerading as fiber optic, I’m talking about the real thing.) And you want to know why I laugh at this entire industry? And for what, to hear Neal Young sing Heart of Gold a little better? How do these people manage to stay in business? Is the whole world stupid?

    • The whole audio world has been advised by irresponsible writers, advertising, trade organizations, and publications acting as shills for the industry. Audio sales reps and retailers continue the myths…and people have bought into it. Unfortunate but true, I’m afraid.

      • Given all of the options people who graduated from engineering school with a degree have open to them in the way of a career, why would any of them choose to go into this industry? Why would they want to design audio amplifiers or DACs when they could be working on exploring space, robotics, nanotechnology, or a thousand other exciting things that are begging for their skills? For me that decision was a very easy one when in my Sophomore year I went to an IEEE show at the NYC Coliseum and saw what industry had in store even way back then. I knew then and there this would only be a hobby for me. I surprised myself at my own ability to make discoveries on my own and to implement them. IMO the people who work building this equipment are for the most part clueless. They keep doing the same thing over and over and over again. I suppose if you can’t tackle anything harder it doesn’t get boring. I think I’d last about a week at most before I went insane.

  11. It’s been a long time since I studied digital and switching circuits but many of the principles remain the same, I have a very good memory, and I received very high grades on a subject I wasn’t particularly interested in. (After all how many times can you look at ones and zeroes until you get gooogley eyed? 🙂 )

    Now as I recall it the first thing a digital signal sees when it gets to a circuit to be processed is a Schmidt trigger. This restores the distorted waveform to a perfect pulse or square wave so that whatever happened along the cable is remediated. Yes there is a trigger threshold and it is very sharp. Slightly too little and you get a zero no matter what the noise. Just more than enough and it’s a one. You aren’t going to get many false zeroes and ones that way. If you do, the noise will be so great that the whole thing won’t work at all. That’s one of digital’s assets, it works just about perfectly or it doesn’t work at all unlike analog systems. After that there is a buffer register that reclocks the signal so any jitter is undone and is as stable as the system clock. To create an error, jitter would have to be so great that the signal falls outside its intended time window for each pulse. In that case again the noise would be horrendous. The RBCD system does have error correcting systems built into it. At the very least it has parity check error detection (all of the digits must add up to a predetermined odd or even number depending on the system. This is controlled by a parity bit that arrives at the predetermined value for each word. From what I could tell reading the RBCD standards, there are others systems built in including request for rereads. Also from what I can tell, the system is broken down into frames where two 16 bit channels actually take up 196 bits. What’s more oversampling should minimize the error created by any one misread for each channel within one frame. So the system has anticipated problems and seems designed to deal with them.

    The article speculates on a lot of theories by different people but I haven’t seen one measurement from anyone to verify that these speculations are valid. Where’s the beef?

    • It is amusing to read all of the comments made by the owners of cable companies. They all use the same terminology without any substantiation.

    • I have been looking at those ones and zeros for 50 years now, but I prefer working on the things you can do with those bits. I remember one of my first digital lab assignments involved building an interface for a teletype ASR-33. That device had a mechanical clock, and it was a speed demon running at 110 bps. If you want to see a noisy digital signal, there is nothing else quite like that mechanical clock, but the digital signal still could be processed, usually without errors.

  12. Can’t someone formulate a simple test to recapture the digital data from different cables and do a comparison between them to put an end to this BS. If the data captured is identical between different cables from different price points then you factually prove that usb cables don’t make a difference thus eliminating the snake oil and ending the debate.

    • I’ve already done it with an expensive USB cable and bargain brand…not data change. Even this level of verification doesn’t satisfy the cable geeks…they make claims of “mixed signal systems”, jitter, and noise…all of which don’t mean anything.

  13. Hi Mark. I’m new here, although I’ve been reading your blog since finding out about it at archimago’s a few months ago.

    It seems that Michael Lavorgna falsely accused you of making up an email conversation with an AudioQuest employee. Has he now apologised?

    • Otto, Michael did falsely accuse me of making up the conversation with a member of the AQ company. I provided the section of the email to prove that I didn’t fabricate or imagine the exchange. He continues to challenge my integrity via comments (he has been blocked from this site) and lately brought up possible legal actions. I have moved on.

      • To be clear, *he* has brought up possible legal actions, regardless that *he* has falsely accused *you*? How does that work?

        • Very weird…I honestly don’t know.

  14. I’m in your school of thought regarding cables but I am at a loss to explain why replacing my $1.89 USB cable connecting a Mac Mini to a DAC with a $24 Pangea USB cable offered dramatically more bass extension and more defined cymbals.

    • Unless the cheap cable was somehow not up to the USB specs, there is no difference…it’s as simple as that. I’ve done the data comparison.

  15. Would an external USB DAC like the JDS Labs Element or Oppo HA-2SE really make a difference if I’m listening to 256+ kbps bitrate MP3 files from my Mac or iPhone?

    • And I’m asking about using the DAC with headphones like the B&W P9. Thanks!

    • Probably not…but it will if you stick with uncompressed audio.

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