MD x Airist x Sosolar: RDAC design mysteries

Discussion in 'Digital: DACs, USB converters, decrapifiers' started by bimmer100, Jun 5, 2018.

  1. 9suns

    9suns [insert unearned title here]

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    This makes a lot of sense.
    However...all that PHD e-peening and they can't even design the board themselves..."talked to my design team"...this means:
    a) lack of comunication...in such a small company with only one product (the Heron 5 amp) in their catalog?
    b) outsourced design team, obviously the Chinese copycats.

    I don't know if they are unfortunate, shameless or dumb, I only know that I wouldn't buy the DAC even if they price it at -10 argentine pesos.
     
    Last edited: Jun 5, 2018
  2. RiddleyWalker

    RiddleyWalker Friend

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  3. bilboda

    bilboda Florida boomer

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    From way out in left field, having seen mfr collaborations of all types with China in the vaping industry, I am guessing they found a board manufacturer who could meet their needs and specs and deliver quickly with small adjustments to a board they had already produced in low quantities and may have been taking a bath on.
    There is no indication that this was exclusively a sosoral device or how much input the mfr had in the final product in the first place. Soren would have experience with this but that may not be directly comparable as his expertise may have required less input from the board mfr to complete the board successfully.
    It would be interesting to know who made the board, and if it is the same mfr, then inquiries could be placed with them. I don't think this is reverse engineered, there is too much to go wrong. It may be as simple as the original board production numbers were too low and the raw product would be available to anyone with a competent business plan.
    Which doesn't mean everybody knew everything that was going on. I'm not ready to throw Airist under the bus yet, but I am happy with my dac 1321 and so won't be ordering the rdac. It does present an interesting notion though. Modular r2r boards available just like dac chips. I wonder what a Schitt custom filter would sound like with a r2r board
     
  4. DrForBin

    DrForBin Friend

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    hello,

    i am under the impression that a requirement to share IP is necessary to do business in the PRC. this has been a topic of discussion in the business press at least.

    if this is so, then it would seem that IP would become commodified.
     
  5. Torq

    Torq MOT: Headphone.com

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    The best part of that discussion isn't the design-origin-drama ... it's seeing one of Amir's apostles, "Jimster480", verbally shitting the bed in a misguided attempt to proselytize the rest of the posters into the "one true faith" ... ASR.

    I've never seen such devotion in a droid before.

    If not a droid, then (s)he/it seems astoundingly zealous, possibly mad and probably has more teeth than brain cells.
     
  6. mscott58

    mscott58 Friend

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    @Torq - Totally agree. Wow, he's almost certifiable. Wouldn't be surprised if he started writing the word truth in all caps, proclaiming that the TRUTH is out there and don't question the TRUTH! I'd also wonder if he has been in and/or started a cult at some point...

    (and for the record, I do not own any Schiit gear and do not make any money from them, just in case the TRUTH-teller is reading this...)
     
  7. dmckean44

    dmckean44 In a Sherwood S6040CP relationship

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    It wouldn't surprise me at all if it turned out neither Sosolar or Airist Audio designed this DAC.
     
  8. zerodeefex

    zerodeefex SBAF's Imelda Marcos

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    The input club dude who caused the big rift was an ex MD employee who knew their margin structure and wanted a bigger cut. If you look at their current efforts, they’re having a hell of a time with manufacturing and quality control as well. I think there are two sides to that story.
     
  9. purr1n

    purr1n Burned out

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    Hahahaha. Exactly why my position is just to buy it. It's such a clusterfuck at this point that there is no sense trying to figure out the disagreements of internal crazy Chinese family matters.
     
  10. rshuck

    rshuck Friend

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    I can actually personally attest to this part, their new products (switches) have the highest failure rate I’ve found.

    That said, I didn’t know that any of them previously worked for MD, which certainly clouds the whole thing.
     
  11. purr1n

    purr1n Burned out

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    I forgot the dude's name; but yeah. IC's narrative, which they themselves pushed out on the Internet, conveniently neglected to mention the ex-MD employee.
     
  12. purr1n

    purr1n Burned out

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    Trending-up-01.jpg
    TRENDING UP - SOSOLAR
    He was the first person to design the board, over two years ago. Evidence of this can be found on Chinese forums along with measurements.


    Compare-arrows-01.jpg
    EVEN - MASSDROP INC.
    A company, privately held. Privately held must mean they are even more evil than publicly held, like run by a Mr. Potter character in It's a Wonderful Life. Offset by the good that they do: providing good shit for a good price to it sucks to be us losers like us.


    Trending-down-01.jpg
    TRENDING DOWN - WILLIAM TSE
    For his weaksauce explanation and thinking that people really are that dumb in the age of the Internet. Also for his common-man Google-Fu skills on providing us plebs with links to how linear series regulators work. I mean, why not linear shunt regulators? MIT and Harvard are ashamed.


    P.S. Arrows provided courtesy of https://www.brandeps.com. Creative Commons thing. Yeah.
     
    Last edited: Jun 5, 2018
  13. bimmer100

    bimmer100 MOT: Holo Audio

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    --------------------------------------------------------My Response below

    Actually, this is not true. It's easy enough to take the code or "CPLD" from the FPGA chip. I've confirmed this with some of my friends who are engineers from many well known companies. And clearly William is trying to change the subject. It's not terribly difficult to extract the code or CPLD from an FPGA like the Xilinx that was used in the Hibiki dac. and code is quite relevant for the specific design. as in...exact layout. Copy and paste = optimized for layout

    Another thing that caught my eye.... William claims he was to show this same dac in late 2015 for the Headfi meet in NYC... yes! he says he brought the r2r dac. the date was Nov 14th 2015. and in october an early release mention was posted on headfi by Mullet- it was posted about this event and what was to be brought to the event.... a quote from William that says... and in reference to the Heron5 amp and the R-2R dac...

    William says, "It will be an integrated system, with digital and analog inputs and in the final version it will have gain settings and outputs for headphones and speakers. The speaker outputs won't be ready in time for the demo but the most important features are in the digital stage and these will be ready. In particular, it will have FIFO reclocking and a discrete 28-bit sign magnitude ladder DAC."

    About FIFO reclocking... NOTE(((SOEKRIS dacs were commonly known for their FIFO Reclocking they integrated into the module. It had jitter reductionby reclocking the signal through a short FIFO or configurable FIFO and reclocked with a lower jitter clock, this eliminated most of the jitter from what I understand." It used a Si514 oscillator that had resolution of 0.026parts per billion. anyhow, more can be read @ https://hifiduino.wordpress.com/2015/01/30/building-soekris-r-2r-dac/

    SOOO in my opinion, the likelyhood Airist's prototype was a Soekris dac at the time, or late 2015 is VERY likely. Their current design doesn't seem to be anything like this. Thoughts?


    reference of post for the late 2015 meeting of headfi in NYC where Airist claims to have the prototype R2R Rdac AKA Sandpiper...here - https://www.head-fi.org/threads/off...tamford-sheraton.779700/page-16#post-12010374

    Hmmm...odd since the dac on MD and Hibiki dac is not 28bit, its 24bit. maybe just a typo...but maybe not. (the good old Soekris had a wonderful 28bit dac that was out at this time... that likely was in that chassis but only an assumption, but what a bummer if they were using that and not mentioning or giving credit to Soekris...if this was the dac used... As i'm not aware of any other 28bit r2r DIY or accessible dac at that time in late 2015-0 but I can tell you the Soekris was VERY hot in the year of 2015, even I built a killer setup with dual soekris boards and many of my friends were into this too, I even knew about the Hibiki board later that year and was following it... No i'm not chinese, GOOGLE TRANSLATE...) And yes... a thread shows my build of a soekris dual dac/balanced setup during the build - HERE - https://www.head-fi.org/threads/discrete-r2r-dac-build-thread.799655/ - HIGH FIVE to soekris! excellent dac module man!!!
    and around Feb of 2015 I posted this...so I would know about R-2R dacs and what was around at this time, I don't recall really knowing much about the Hibiki dac until later that year and discussing it with some close friends.

    (((((NOTE: Soekris dacs at this time was THE CHOICE to those commercial companies wanting a r2r module for their own dac design, it was common place to do and think about this at this time...for instance...take note of the Lessloss dac which uses soekris dac, and the vineshine dac that also uses soekris, these are commercial dacs, or how about the Acuhorn Streamer with the soekris dac? I can go on... point is... Airist maybe was considering soekris 28bit r2r at this time, and a prototype idea could of been to use this module in their dac... sounds reasonable?)))))

    but later in the thread above (last link), Airist comments on Mullet's post to confirm it's correct...so not a typo... So Airist brought a 28bit R2R dac to the event, NOT the design they are selling on MD...however confused or being said is the early design or prototype? hard to believe...
    here is link to confirm. dated Nov 9th.
    https://www.head-fi.org/threads/off...tamford-sheraton.779700/page-22#post-12063578

    anyhow, here is the thread with "impressions" for this event
    https://www.head-fi.org/threads/official-nyc-fall-2015-regional-meet-impressions.787569/

    Here is a post from airist - Nov 18 2015 saying their dac is 6-12months out and the dac at that show was a prototype. - https://www.head-fi.org/threads/air...black-friday-sale.787946/page-2#post-12087027

    So to recap again... at this time frame of late 2015...Airist has a 28bit ladder dac in a chassis and nobody saw this dac as far as I know. CLEARLY not the same dac as (Matt) Baitao Chen's Dac, the Hibiki dac. as this dac is not the same, it's a 24bit dac. and if Airist can prove they had this design back in October of 2015, this story can take a turn...however, not likely.
    also, would be nice if someone had one of these MD Airist Rdac's on hand to look at the bottom of the PCB. as this also is relevant. But here is the bottom of a Hibiki R-2R
    http://f1.hifidiy.net/forum/201606/16/123702gja87awvah7wswsh.jpg

    William Tse said he went to school for math and statistics...I would like to know the statistical possibility and/or probability that their dac design happens to coincedently match 99.9% of the component positions and layouts along with identical measurements of the board and traces etc. overall proportions to just randomly happen to be the same. What is the statistics of probability for this to happen? Is this even possible? The short of it, not likely.
    ------
    back to (Matt) Baitao Chen's Dac...aka Sosolar. Who made the dac first? Airist /William Tse or Sosolar?.

    thread here - http://bbs.hifidiy.net/thread-1149252-1-1.html
    http://f1.hifidiy.net/forum/201512/15/134202op3xxfpdzzxpppk1.jpg

    shows and dates to finished products around Dec 15th, but he already had been working on these designs for about 2 months... soo roughly october 15...

    but showing renderings of the final design, or early design rather without the LED's for each channel as in the v1.2 models or the one Airist is using. Currently for sale on Taobao from Sosolar's store. and the current MD version happens to have the later revisions of the Hibiki to be applied to the design. in the exact spots. yes... coincident? sure, that sounds statistically possible... but in this regard I suppose so, they fit nicely there. :D - almost as if the plan was originally to have them there but decided to remit them and focus on a prototype board with LED's not being critical to the design element in the beginning trials. Sounds logical to me.

    hmmm..
    anyhow, i'm confident that (Matt) Baitao Chen will have this worked out.

    My one concern to those who want to buy this MD Airist R2R unit.... It's not really about legalities anymore as it is about ethics and integrity or personal values of what is right and wrong. For those who want to just BUY the unit and not care about the people who put their blood sweat and tears into the product...well that's a clear statement to your own character and my opinion won't mean anything to you anyhow. I would hope those would want Sosolar to get proper credit for his design and not support a company who would not give credit where it's due. Who cares if the dac drops tomorrow or not. Ethically it's wrong to release this dac and ignore Sosolar and his hard work... Please just consider for a moment what it takes to design and build one of these dacs.

    Maybe MD and two parties can come to fair agreement. Everyone wins? but i'm only crossing my fingers. And only the above is observations I have made.
     
    Last edited: Jun 6, 2018
  14. purr1n

    purr1n Burned out

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    Damn. Looks like this Tse dude is looking more and more like a real turd. Maybe he really didn't know the 24-bit board in the RDAC was ripped off from Sosolar, but the half-truth narratives in his explanation, leaving out important details like how he switched ladder boards from Soekris (at NY meet) to the "unknown" Sosolar board at a later date (or what was unknown then) really irks me.

    Yeah, if Tse can prove he had the boards circa Oct 2015, that would change everything. So far, I don't like the smell.

    This is good Vanity Fair, err Vanity Ear stuff.

    I don't think it's fair to lay the ethics stuff on the consumer. Consumers will do what is cheapest or most convenient. I know for a fact that 99% here have music in their collections that they did not buy - in other words, the music was stolen. The only people exempt might be the CD and vinyl spinners.

    I now have mixed feelings about the RDAC. Feels icky. Like a bad karma bomb waiting to go off.
     
    Last edited: Jun 6, 2018
  15. willsw

    willsw Friend

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    [​IMG]
     
  16. bimmer100

    bimmer100 MOT: Holo Audio

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    https://www.massdrop.com/buy/massdrop-x-airist-audio-r-2r-dac/talk/2100186

    william says
    "The circuit elements in place, we had to put everything together on a board. R-2R DACs can be sensitive to noise, so it’s important for the component layout to have short paths. We worked with a consulting engineer for this and he looked at a number of existing boards for a baseline, including the MSB, Soekris, and several more that he researched. This included an early version of the Hibiki that he came across on the Chinese audio forums, as well as various open source boards. From there, he laid out our board with a ground layer to further manage noise in the circuit. This 4-layer PCB eventually became the top board of the RDAC."
     
  17. willsw

    willsw Friend

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    The new response includes the details that we needed and suspected anyway: they hired a guy who gave them a board based on their parameters. That the layout was taken exactly from the Hibiki was out of his hands. Responsibility successfully passed on. DSP and upsampling discussed, giving him back some designer cred. Probably was avoiding that so as not to scare off people who are ideologically looking for a non-oversampling DAC.
     
  18. Baten

    Baten Friend

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    This, in a nutshell. "Don't blame/sue us, blame the consultant we hired for the board".
     
  19. JustAnotherRando

    JustAnotherRando My other bike is a Ferrari

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    That "blame the consultant" line was hidden in the middle of 7 paragraphs of distractionary and completely irrelevant technobabble. Nor does he acknowledge that it's pretty much a 1:1 copy, instead he mentions a couple of other 'inspirational' sources for the design.

    Everything about Airist, from the Heron to this RDAC, seems more than a bit off.
     
    Last edited: Jun 6, 2018
  20. purr1n

    purr1n Burned out

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    Looks like my crystal ball was right.

    Fuck that dude. He could have come right out with that in his first response instead of playing "match the two boards of the five - but they all look the same to me".

    Maybe his first response should have been "This is alarming, we are looking into it. We relied on a consulting engineer for the board design. If Sosolar's claims are true, we will make it right."

    Don't know how a guy from Harvard can be so dumb. Maybe he outsourced the degree too. Zero credibility.

    P.S. Good work guys for the investigative research. The newspapers of decades ago would be proud.
     
    Last edited: Jun 6, 2018

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