Dr. AIX's POSTS — 28 September 2015

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The past week has been filled with encouragement from friends and supporters of the Kickstarter campaign. Funding has reached almost 150% after a single week. Thanks to everyone backing the writing of the book and the production of the demonstration files. If anyone has any specific topics, demo tracks, or audio samples they want to see me tackle…just let me know. Other than the doubts expressed about my skills as a recording engineer by a novice engineer at CA and within a few comments on this site, everything is going great.

So why would I want to revisit the whole Regen thing and the major push back that I got from several audio writers? Because there’s some additional information…some very rigorous analysis…over at the What’s Best Forum by the site’s founder and administrator Amir.

He is careful to point out that his analysis is located in the SCIENCE section of the forum. He didn’t focus on a subjective listening evaluation and then report on his perceptions. Instead, he did a variety of analyses using his Audio Precision and posted the results in the article. Amir’s approach is to be applauded although I’m sure that the subjectivists will continue their crusade and continue to push the non-scientific approach to better sound. And I know it has its place…what we hear is all that really counts. But I for one like to know that what I hear has some reasonable and rational basis in the science of digital audio recording and reproduction.

You can read the article and review his plots by visiting the WBF at Review of Audioquest Jitterbug and Uptone Regen USB Conditioners.

Amir wrote the review because he was curious. He admits to being an amateur reviewer. He included the Audioquest Jitterbug in his review…another piece of equipment that I haven’t yet had the chance to explore but which falls in the category of an unnecessary audiophile tweak for me. And Amir’s conclusions support this belief.

The stated purpose of these types of products is to correct or clean up the digital information on the USB bus as it heads from your source to DAC for conversion. There is every possibility that the data and power on a USB bus is less than perfect…that is surely the case. And it’s the noise in the transmission of digital data that the Jitterbug and Regen try to address. But wouldn’t a quality DAC clean up the incoming data without the need of these units?

Amir states, “I sure hope anyone buying a DAC is getting one where the designer knows very well that these issues exist and has already put the few cents or dollar or two worth of parts that these products have. As such, I personally don’t expect any high-end DAC to benefit from these products. If any do, I would question the DAC company before resorting to dangling a device like this in front of them.” Sound familiar?

I’ll let you read Amir’s very well written conclusions but essentially he agrees with my assessment of these devices. Here’s the quick of it, “Simply put, there is no good news here. Both devices degraded the performance of the DAC a bit and did nothing to improve it. There are reasons for this that I won’t go into but let’s be careful in using our intuition that when something is ‘filtered,’ it is always good. That is not how this interface works.”

So do I feel vindicated? No, this is not a competition. I felt confident in my assessment before and I’m pleased that a careful analysis using a very rigorous procedure and expensive Audio Precision software didn’t contradict my position. The sad part is that it will not cause the other side to change their position…which is unfortunate.

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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.

(25) Readers Comments

  1. Mark,

    I continue to believe and admire the “bits is bits” philosophy but I don’t care what the fancy software says, I have a Jitterbug and do believe that it has made an audible and noticeable difference, so I trust my ears and my listening preference. I ended up with five of them, one for the NAS, one for the router, one for each of my computers and one in the car. In every case the music just seems more relaxed and musical. I find myself tapping my toes at the music more and able to listen for longer periods. For the small and modest amount these cost me I am well satisfied. I honestly think that some things can just not be measured, but certainly exist. By the way, every piece of gear (other than the car) I have played these through has been on either Stereophile’s or The Absolute Sound or Sound and Vision’s recommended components list, so, it’s not the best, but certainly good enough!!

    • No one should ever tell that you can’t purchase and enjoy every possible audiophile tweak. The point that myself and others are trying to make is that there is no technical benefit that can be identified using the best analytical tools available. The bits are not changed, the noise doesn’t affect the readability of the bits, and the clock (jitter) are not in play when using asynchronous USB…so it’s your subjective evaluation that has to count. I haven’t had the chance to listen to a jitterbug…but my experience with the Regen was enough to convince me that the device doesn’t do anything to improve the sound…at least of my recordings through my system. The AP plots verify this.

  2. Can you hear that, the sound of some one hitting a bee hive with a stick. LOL
    Seriously it is so good to hear another voice of reason among all the chaos.

    IMHO HiFi is in big trouble today. To most audiophiles the only important thing is if the component in question sounds good to the listener. Said listener doesn’t have to prove what he thinks he hears is real, to even ask him any more is heresy. If Mr Audiophile says A sounds better than B, then it just does, and a horse-pile of excuses are made as to why any kind of tests are not relevant, again only the ear matters Accuracy no longer matters, measurements not only don’t matter but are despised and seen as the enemy. How is the art of High Fidelity reproduction to progress when a large portion of those involved in the hobby care more about chasing ghosts in things like the Regens, AC cords, USB cables, SR dots, and all the rest of the snake oil being peddled as major improvements in sound.
    Nobody expects the spanish inquisition

  3. I’m glad you revisited the Regen and Jitterbug USB conditioners topic. It’s a clear case of scientific measurement vs. subjectivism/observation, a never ending debate in our wonderful hobby.

    Amir said in his article, “I personally don’t expect any high-end DAC to benefit from these products.” Well, this begs the question, do these devices benefit low-end DACs? And that may be the more relevant question as there are a lot of inexpensive DACs in inexpensive digital systems and this is the natural market for inexpensive conditioners.

    I recently added a Jitterbug to my laptop and Audioengine 2+ powered speakers music system. At $249 per pair for decent speakers with built-in amp and DAC, then the DAC surely must be considered low end.

    My subjective opinion is the Jitterbug improved the music. Did it improve it a lot? No. I was happy with the sound before, but I am even happier with the Jitterbug in the system. Would it have been a cost effective tweak if the Jitterbug were expensive? No, but at $49 it is a reasonable tweak for this system.

    Bottom line: Let’s check out these devices in systems where they have the best chance to succeed.

    Phil_C

    • The same idea was contributed by John Siau of Benchmark. If the designer of a good quality DAC has done his or her job, then devices like the Regen and Jitterbug should be necessary. Whether they will help a poor design is not terribly interesting to me. We’re supposed to be audiophiles. We’re supposed to care about the gear and content in our systems. Why would you purchase a poorly designed DAC and then spend $175 trying to tweak it to another level? Just get a good quality DAC to start.

      I can’t and wouldn’t try to explain subjective reports that the Regen or Jitterbug improve the fidelity of your music. There is no technical or scientific reason why that should be the case. The bits are unchanged and the clock is newly created in the DAC. The signals coming out to a good DAC with and with the devices is actually less distorted when the devices are left out of the chain. Go figure.

  4. I bought a Jitterbug, as the dealer I got my used Benchmark Dac2 HGC, was very enthusiastic about it. I put it in and just left it there for weeks. I finally removed it, used Lucinda Williams “Blessed” CD I had ripped to JRiver, I’m using a PC, so no Amarra.
    I wasn’t expecting any audible effect, as I have been reading your reasoned explanations on why it shouldn’t.

    Well, it removed a layer of glare that was so obvious, I didn’t have struggle or question what I was hearing. Why it works, don’t know, but I got better sound. Based on “bits are bits” CD transports should not make a difference, but I have heard real differences when changing transports, so I have to believe everything in the digital path matters. It may not have anything to do with the bits, and a lot to do with the noise being carried along with those bits.

    I’m keeping my Jitterbug, the improvement I got, would have been worth a lot more than $50.

    • Glad you like it…my system sounded the same with or without the Regen. I’m not going there.

  5. Hi Mark,

    I have been following the astounding success of your KS campaign; my compliments and congratulations. I have already signed up for my copy and I am really looking forward to it.

    I have two suggestions for important topics to be covered by the AudioGuide:

    1. The most substantial bottleneck to experience the potential advantages and merits of HRA, aside from widespread poor recording practices, is the very limited equipment available for both recording and reproducing HRA.

    A comprehensive list of microphones, microphone preamps, A/D & D/A converters, power amps, speakers, headphone amps, headphones, players, etc., as well as the necessary and sufficient specs to look for, would be useful and significant information for a comprehensive discussion on HRA, and certainly part of an exhaustive and objective audio guide.

    Such a list, and a solid criteria regarding specifications, would also set things straight regarding the misleading lists of recommended equipment that audio and hifi magazines regularly publish, and which aren’t really based on rigurous criteria at all. Even a section with actual independent measurements of audio components would be fantastic!

    2. Most recording labels, including those with the best recording practices today, do not provide sufficient information on the recording process and gear used on their productions. Very few provide a succint list of the equipment used, and even fewer offer some minor hints regarding the actual process of recording. As far as I know, no label provides some kind of analisys of the recordings they make, such spectagrams or dynamic range, in order to really guarantee HRA quality.

    A comprehensive list of record labels – and maybe even engineers – that really are in the business of producing true HRA recordings, as well as more specific information on the practices that some of them use, in respect to their merit when it comes to HRA. You have mentioned that you are working on a data base of HRA recordings, and this is a truly valuable resource for consumers and professionals alike. Including that information to the AudioGuide would be very significant.

    ————————————————————————-

    Both recording and reproducing true HRA is fairly expensive; keeping an HRA capable stereo rig – let alone a multichannel rig – below 30K is virtually impossible, and one would be equally hard pressed to keep a basic HRA capable stereo recording setup below 10K.

    On the other hand, simply spending more is not going to get you there either, which is what hifi and audio magazines try to make consumers believe. That is what they really push with their lists of recommended components. I believe this is something that needs to be sufficiently acknlowledged. I have insisted on this matter in various comments, as I believe the equipment capable of recording and reproducing HRA is limited to extremely few components, and even the most careful practices and correct techniques, along with minimalistic mixing and mastering, could fail if the equipment used to record isn’t really capable of capturing HRA.

    Knowing how record labels record the music we buy, and how they come up with the final product, is as important as having the proper labels on the food we buy at the supermarket. If I pay extra for organic products, I want to know that there’s a certification that can guarantee that the products comply, and obviously know the guidelines of that certification, as you have clearly shown that the music and recording industry today, has purposefully created false guarantees to deliberately fool and mislead consumers.

    A minimum of quality control is absolutely in order, and if we don’t have access to the tools or the expertise to verify by ourselves what we purchase, a database with that iformation is really fundamental for music consumers today.

    Thinking about the good positive impact that your AudioGuide will have on music consumers, I can’t help but to imagine what a RecordingGuide aimed at musicians could do. They need to know a lot more about recording practices and quality differences, and they could have an equally or even more powerful and direct impact on the industry today.

    Cheers!

    • Very good comments…this is a keeper.

  6. I read Amir’s article referenced at this site. Amir clearly puts a lot of stock in high-end DACs getting the job done properly and taking care of all the nasties that may come down the USB cable from the computer.

    Given his negative findings and comments about the Regen and Jitterbug, one might be left with the impression that he is against all USB conditioners. Interestingly, this is not the case; Amir does advocate a couple of USB bridges at his Madrona Digital Home Theaters, Audio and Video website in a posted article, “Building High Performance Audio Servers” at this URL:

    http://www.madronadigital.com/Library/High%20Performance%20Audio%20Servers/High%20Resolution%20PC%20or%20Mac%20Music%20Servers.html

    I don’t want to misrepresent Amir in any way with my brief summary statements that follow, so be sure to read his entire article.

    Basically, he thinks that a proper DAC should be asynchronous to eliminate clocking problems and have galvanic (electrical) isolation to eliminate noise through the USB.

    With that in mind, he goes on to say, You have two choices here. You can get a new DAC or AVR with a built-in asynchronous USB interface or buy a “bridge” adapter that converts USB asynchronously to S/PDIF (and its balanced professional AES/EBU counterpart if you have that in your DAC). My preference is for the bridge as that gives you much more choices of AV products including the DAC/AVRs you already have. There are many such interfaces at all price points. In this article I will be talking about two of my favorites:

    1. Berkeley Audio Design Alpha USB adapter. This is a very high performance bridge that takes USB input and produces either S/PDIF or AES/EBU. It has a built-in power supply that is a must for clean power as opposed to trying to use the USB power.

    2. Audiophilleo USB to S/PDIF adapter. This is another well designed product which is small enough to couple directly to the S/PDIF connector.

    Amir’s measurements showed these conditioners to work. Of further interest, notice that both these conditioners have in common that they switch the signal from USB to S/PDIF or AES/EBU interfaces before sending the signal on to the DAC. Also, the Berkeley has its own power supply to avoid using the USB power. The Berkeley costs $1895 and the Audiophilleo is $999.

    Phil_C

    • Thanks Phil…I haven’t read the article yet but I will. Converting from a USB bus to S/P DIF or AES is something completely different than “regenerating or cleaning” a USB stream. I’m actually surprised that they would be called “conditioners” instead of “converters”, which is what they actually do.

    • Amir’s article is interesting as it does demonstrate potentially audible differences in the analog output of a DAC processing a J-Test signal (12 kHz) provided by HDMI, USB and USB converted to S/PDIF PC outputs.

      However, there are problems in reconciling the graphs Amir provides some of his conclusions. In each of the graphs where he is comparing 2 options, he consistently overstates the superiority of the better performing option. Also, the frequency range is different for each graph, making it difficult to compare the graphs.

      For example, in the first graph Amir compares the output of a Mark Levinson 502 Processor using HDMI input to S/PDIF input converted from USB. This graph covers a frequency range of 4353.52 Hz to 20,000.00 Hz, and his quality criteria is the largest dBFs spike. He correctly identifies the highest HDMI spike of -114 dBFs at 7200 Hz with the USB-S/PDIF spike at -127 dBFs, but he ignores the highest USB-S/PDIF spike of -121 dBFs at 11800 Hz with the HDMI spike at -124dBFs. Based on the single chosen HDMI spike he states that USB-S/PDIF is 13 dB better. In the second graph the frequency range is 11000 Hz to 13000 Hz (What’s happening in the rest of the audible frequency range?), the highest HDMI spike of -84 dBFs at 11900 Hz (USB-S/PDIF: -103dBFs) is identified and the highest USB-S/PDIF spike of -96 dBFs at 11760 Hz (HDMI: -96 dBFs) is ignored. Based on the single chosen HDMI spike he states that USB-S/PDIF is “nearly 20 dB” better. If the first graph had been restricted to the frequency range in the second graph, it is possible that HDMI would have appeared to be the better performing option.

  7. CORRECTED VERSION!

    Hi Mark,

    I have been following the astounding success of your KS campaign; my compliments and congratulations. I have already signed up for my copy and I am really looking forward to it.

    I have two suggestions for important topics to be covered by the AudioGuide:

    1. The most substantial bottleneck to experience the potential advantages and merits of HRA, aside from widespread poor recording practices, is the very limited equipment available for both recording and reproducing HRA.

    A comprehensive list of microphones, microphone preamps, A/D & D/A converters, power amps, speakers, headphone amps, headphones, players, etc., as well as the necessary and sufficient specs to look for, would be useful and significant information for a comprehensive discussion on HRA, and certainly part of an exhaustive and objective audio guide.

    Such a list, and a solid criteria regarding specifications, would also set things straight regarding the misleading lists of recommended equipment that audio and hifi magazines regularly publish, and which aren’t really based on rigurous criteria at all. Even a section with actual independent measurements of audio components would be fantastic!

    2. Most recording labels, including those with the best recording practices today, do not provide sufficient information on the recording process and gear used on their productions. Very few provide a succint list of the equipment used, and even fewer offer some minor hints regarding the actual process of recording. None provide information about digital processing, muxing and mastering, aside from the name and place of the studios and engineers. As far as I know, no label provides some kind of analisys of the recordings they make, such as spectagrams or dynamic range, in order to really guarantee HRA quality.

    A comprehensive list of record labels – and maybe even engineers – that really are in the business of producing true HRA recordings, as well as more specific information on the practices that some of them use in respect to their merit when it comes to HRA, would be very significant in my opinion. You have mentioned that you are working on a data base of HRA recordings, and this is a truly valuable resource for consumers and professionals alike. Including that information to the AudioGuide would be very significant.

    ————————————————————————-

    Both recording and reproducing true HRA is fairly expensive; keeping an HRA capable stereo rig – let alone a multichannel rig – below 30K is virtually impossible, and one would be equally hard pressed to keep a basic HRA capable stereo recording setup below 10K.

    On the other hand, simply spending more is not going to get you there either, which is what hifi and audio magazines try to make consumers believe. That is what they really push with their lists of recommended components. I believe this is something that needs to be sufficiently acknlowledged. I have insisted on this matter in various comments, as I believe the equipment capable of recording and reproducing HRA is limited to extremely few components, and even the most careful practices and correct techniques, along with minimalistic mixing and mastering, could fail if the equipment used to record isn’t really capable of capturing HRA.

    Knowing how record labels record the music we buy, and how they come up with the final product, is as important as having the proper labels on the food we buy at the supermarket. If I pay extra for organic products, I want to know that there’s a certification that can guarantee that the products comply, and obviously know the guidelines of that certification, as you have clearly shown that the music and recording industry today, has purposefully created false guarantees to deliberately fool and mislead consumers.

    A minimum of quality control is absolutely in order, and if we don’t have access to the tools or the expertise to verify by ourselves what we purchase, a database with that iformation is really fundamental for music consumers today.

    Thinking about the positive impact that your AudioGuide will have on music consumers, I can’t help but to imagine what a RecordingGuide aimed at musicians could do. They need to know a lot more about recording practices and quality differences, and they could have an equally or even more powerful and direct impact on the industry than consumers.

    Cheers!

  8. You make a good point Dr. AIX when you distinquish between conditioner and converter.

    I have been thinking of conditioner, converter, adapter, and bridge as synonyms but I guess they are not. Looking back at Amir’s article, “Building High Performance Audio Servers” he did not label the Berkeley or Audiophilleo a conditioner as I did in my post. Rather he used the labels converter, adapter, and bridge adapter.

    Phil_C

    • Thanks Phil. Converting an asynchronous USB data stream to an S/P DIF or AES-EBU standard digital signal is something that I would support. It would take a very high degree of engineering prowess to do it right.

  9. I bought a Jitterbug a few weeks ago, mainly on the recommendation of John Atkinson editor of Stereophile whose judgments I tend to trust (though as a PhD physicist, always with some scepticism) from his reviews of equipment and music with which I am familiar – and because, in addition to listening, he does measurements (I think he has a science background) a philosophy as a speaker designer for 25 years (including with Linn Products in Scotland) I wholeheartedly agree. John’s review of the Jitterbug was something along the lines of ‘my measurements don’t show any difference but I hear a difference which I like – but don’t like/understand the difference between measurement & listening’.

    I am not an electronics engineer but have picked up some understanding of it over the years – since I measured the characteristic curves of valves in Physics 2 at UniMelb! I accept the theory/measurements that ‘bits are bits’ so the amplitude axis cannot be affected but understand also that the time axis of the waveform may be affected by what is commonly called ‘jitter’ presumably by sharpness of leading edges etc.. I also understand that in principle a perfect DAC should compensate for it – but no electronic piece is perfect! I certainly found a significant improvement in an Audiophilleo USB-SPDIF converter when inserting an Aquavox unit into the USB connection (replacing the USB power supply by a high qualitylinear one).

    My current DAC is part of a DEQX HDP4 dsp processing unit and I know from talking to Alan Langford of DEQX (you can visit him at this year’s RMAF) that they spent a lot of time and money on power supply filtration of their USB-SPDIF converter. However because the Jitterbug was cheap, from a reputable manufacturer, and because I thought ‘one cannot have too much power supply filtration’ – and because of John Atkinson’s comments – so I thought I would try it.

    I put the Jitterbug in series with the USB lead to the DAC about 3 weeks ago and have been playing through it uncritically while I have been developing a new passive speaker – uncritically because my first impressions were that it did not make a lot of difference but also because I wanted to be sure there were no ‘burn-in’ issues. However yesterday I did some more critical listening through my reference system – a 4-way active speaker system controlled by the DEQX HDP4 processor (it is an upgrade of the 3-way Tikandi system we demonstrated with some acclaim at RMAF 5 years ago). The system has very low THD for a speaker (around 0.1%) & very flat response (+- 1dB) over much of its frequency range and has excellent micro- & macro-dynamics. More details are given at http://www.legendspeakers.com.au/tikandi_grande_Be.html

    So did I hear a difference with the Jitterbug in place compared without it? Definitely! Was it better? Not to my taste!

    I listened to 3 tracks to try to cover a variety of music styles:
    Handel’s Messiah ‘And the Glory of the Lord’ – for choral and orchestral
    Jackson Browne ‘Walking Town’ – pop
    Dave Brubeck ‘Take Five’ – jazz
    In all cases it was like adding a bit more contrast (to use the sight analogy) which some people might find more attractive, particularly if their systems are a bit dull. And the Jackson Browne might be thought to be more dynamic/sharper. But to my taste they sounded less natural – and in the case the Messiah too sharp/hard. This is may be consistent with Amin’s findings that the Jitterbug adds some high order distortion – in the same way that low order, particularly 2nd order, distortion from valve amps, cartridges etc can make the sound more ‘euphonic’.

    Any they are my 2c (or more) – I accept that others may have different tastes!

    • I need to be convinced. Subjective or anecdotal descriptions don’t sway me…especially if I’ve experienced audio “enhanced” by devices at any price level. It’s not worth $50 or $175 or any amount if it doesn’t do anything…technically to the signal. That’s just my thinking. You need to download the tracks from my FTP to hear what real HD-Audio sounds like. You’ll hear more through your speakers.

      • I guess some people don’t want to be convinced unless they hear it themselves – and don’t trust others’ judgments even if they also have a lot of experience!

        I have already downloaded a number of AIX samplers over the years – and think the recordings are generally great. I even have an early DVD-Audio sampler of yours that I can play – along with a few other DVDAs – on a Denon 2910 at 96/24 output. And I have ripped all of my SACDS (some 100+ of them) to 88/24 wav files plus have bought some true hires (recorded at 88/24 or greater) download FLAC files from Linn, 2L, BIS etc…………

      • Dear Mark,
        I am planning to switch from spdif to HDMI..
        This article http://www.madronadigital.com/Library/DigitalAudioJitter.html made me question my prior (and still current) beliefs about the integrety of digital signals over e.g. cables.
        I feel that something is not wright in the reasoning, but I cannot pinpoint the weakness.
        What’s your opinion on the audibility of jitter and the case made on that page?

        • I’ll take a look at the article…and respond.

  10. Watched the Full Truth Behind Behind High-Res Audio on AVS Theater today.
    http://www.avsforum.com/the-truth-behind-high-res-audio/
    Excellent job of getting the full word out there to a large audience. Anyone who hasn’t
    seen it yet should take the time out.
    Thanks

    • Michael,
      From your review of the REGEN, you say the REGEN “[delivers] a cleaned up impedance matched signal to your DAC”. While Mark’s comment is that the REGEN “corrects or cleans up the digital signal…from source to DAC…”.

      Ok, Mark’s sentence is not as precise as your sentence in your review, but the main idea seems pretty close to me as a consumer. Mark is not writing a review, so I don’t expect him to include the details of the REGEN functions…reducing packet noise, perform impedance matching, or improving signal integrity…in one sentence every time he responds about the REGEN in a post. I don’t see his statement as misleading; if one wants more detailed information, they would go to your official review or the UpTone Audio website.

      • Thanks Todd. I think the point was made and I’m glad that Amir was able to show through analysis that the Regen actually doesn’t do these things. It certainly doesn’t modify the sound…at least in my studio to these ears.

  11. Hi Mark,

    This topic never gets old, does it 😉 A few things re. Amir’s post; The folks at the What’s Best Forum have renamed that SCIENCE section since they are admittedly not conducting science. It is now more appropriately named “The Measurement Based Audio Forum”. While Amir’s measurements are interesting, they are in no way conclusive and a few people in that thread have pointed this out. Of course we are free to believe whatever we want, but it should be noted that a belief is still a belief even when you put science in ALL CAPS.

    You say, “The stated purpose of these types of products is to correct or clean up the digital information on the USB bus as it heads from your source to DAC for conversion.” This is not the stated purpose of these products and I am frankly surprised to see that you have not yet grasped this fundamental fact. No wonder you believe these devices are ineffectual!

    See you in Denver!

    Cheers.

    • Cheers Michael…see you there.

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