Dr. AIX's POSTS TECH TALK — 06 September 2015

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As usual, I’ve been spending way too much time at this computer today. I did manage to break free for a couple of Frisbee sessions at the part down the street with Charlie. He’s had quite a day with an early morning 4-mile run and follow up Frisbee session and two additional times this afternoon. He’s likely to get a bike ride around the neighborhood if I get home in time.

I’ve been trying to polish up the rapidly approaching Kickstarter Campaign. I spent yesterday creating the 30″ video that is now on the Music and Audio landing page. You can check it out by clicking here. Any feedback is greatly appreciated. Believe it or not it took the better part of a day to produce just 30 seconds.

Tomorrow Russ brings his friend’s REGEN box, his Benchmark DAC2 and a few other cables and such. I’ve invited a few LA and OC Audio Society friends to come and participate in the evaluation of the device. I should say right out front that there is nothing scientific or publishable about what we’re going to do tomorrow. This is meant to be a casual check of several basic things. For those that have been writing saying that the test is meaningless, think what you want.

Here’s how I see things going. We’ll have a single Mac Laptop playing one of my high-resolution 96 kHz/24-bit tunes in stereo. I would prefer to use Amarra because I believe it does the best at playing back the digital information. I have listened to JRiver, Audioirvana, iTunes, and Amarra and Amarra comes out sounding the closest to what I know my tracks sound like.

The USB outputs from the Mac will be sent via a couple of good USB cables to the two Benchmark DAC2s for decoding. We’ll do it first without the REGEN box in between the Mac and the Benchmark. The analog outputs will be sent to the A|X Box that Russ has and then to a Butler Amplifier into two of my B&W 801 Matrix III speakers. These are the speakers that I’ve owned for years. I would prefer to use HRA speakers but I can’t afford to purchase 5 of the JBL M2s.

We’ll listen to this setup and compare the sound. As you would expect, there shouldn’t be any differences. We’ll carefully level match the two devices (I have an SPL meter and I believe there is CAL setting on the Benchmarks). Then we’ll put the REGEN box in between one of the two setups. And do some additional listening. There’s no time pressure…the people here will have plenty of time to make there choices.

I’m going to capture the output of the Mac with and without the REGEN and do a polarity reverse in one file. I’m going to see if they null each other. If they do, it will show that the digital data coming from the REGEN and straight from the computer are identical. For me, that’s proof enough that the DAC will produce the exact same analog output signal. We’ll see.

Gotta go.

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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.

(14) Readers Comments

  1. Mark,

    I did not give you permission, nor did you bother to ask, to use my photograph of the REGEN. Please remove it from your site.

    If “bits are bits” please explain how Amarra, JRiver, and Audirvana can sound different even though they all deliver bit perfect data.

    • The photo has been removed.

      • Thanks Mark.

        Re. your “test”, you have already put the following stakes in the ground (these are all quotes from you):

        “But is the REGEN going to make a difference in a truly high-end system? No, it won’t.”
        “Although, I’m willing to accept that the REGEN and devices like it may work for some people that have substandard gear.”
        “Over the years since I first met him [John Siau of Benchmark], he has become a friend and one of my goto guys when it comes to the technical merits of this or that system, format, or accessory.”
        “Tomorrow Russ brings his friend’s REGEN box, his Benchmark DAC2 and a few other cables and such. I’ve invited a few LA and OC Audio Society friends to come and participate in the evaluation of the device.”

        You want us to believe that you are going to provide an unbiased “test” of a device you know won’t work, played through your friend’s DAC, which, if you admit to hearing a difference with the REGEN, by your words is necessarily “substandard gear”.

        That’s about as big a hole as any I’ve ever met. It will be interesting to see if and how you can dig yourself out of it.

  2. Interesting… All of the media players you mentioned are claimed to be capable of producing output that is bit transparent to the source file. Here, at least, is an opportunity to use the inversion of the digital data to check. Or, are you satisfied that Amarra is better, because it sounds better to you?

    • There have been a lot of questions about the “bits are bits” issue and player software. I will write an entire post on this asap.

  3. Dr Waldrep, I value reading your blog each morning, and your quest to cut through the layers of misinformation regarding high fidelity music recording.

    I have one question about your testing, above, that caught my eye. You mention in this posting that the playback software makes a difference in how your track sounds, and that Amarra is the one that “sounds the closest” to what you expect. What do you think causes the software application to have an effect on the track? Isn’t it just sending commands to feed digital data from the hard disk into the DAC? Have you ever done the reverse polarity test with different software apps to see what, if any, changes the app is causing to color the listening experience?

  4. Might be worth assessing the digital output from your mac when your tracks are played back via jriver iTunes Amara etc

  5. Mark, with regards to the player software, aren’t all those players delivering the same bitstream to the DAC? If you capture the bitstream out of them and they cancel, that would mean they should sound the same.

  6. “I would prefer to use Amarra because I believe it does the best at playing back the digital information. I have listened to JRiver, Audioirvana, iTunes, and Amarra and Amarra comes out sounding the closest to what I know my tracks sound like.”

    I would surmise then that these media players aren’t delivering a bit perfect data stream to the USB port? If they were, they should sound identical no?

  7. If we are saying that ‘a bit is a bit’ – a sentiment that I whole heartedly agree with, then I am intrigued to know how the software used to transmit those bits from computer disk to USB (JRiver, Audioirvana, iTunes or Amarra) can be said to make a difference to the music reproduction!

    If the ‘bits are just bits’ then nothing between computer hard disk and eventual DAC should make any difference.

    Just a thought!

  8. Mark,
    You wrote “I would prefer to use Amarra because I believe it does the best at playing back the digital information. I have listened to JRiver, Audioirvana, iTunes, and Amarra and Amarra comes out sounding the closest to what I know my tracks sound like.”

    If bits are bits and these players are all bit perfect players with no EQ or DSP engaged, why would one sound better than the other?

  9. I have a feeling the Amarra statement was off the cuff!

    • I’ve known the work of Andy Moorer, one of the world’s most respected DSP and digital audio gurus, for more than 30 years. He’s the guy behind Sonic Solutions and a close associate of the engineer in charge of Amarra. I’ll be asking Jonathan Reichbach for his thoughts on why the Amarra software works and sounds so good.

      • I asked John Reichbach and seven other media player developers including JRiver and Audirvana this very question (and 9 other questions) on AudioStream 3 years ago.

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