Schiit Yggdrasil Less is More (and MIL and OG) Impressions + Measurements

Discussion in 'Digital: DACs, USB converters, decrapifiers' started by purr1n, Sep 9, 2021.

?

Should SBAF get a loaner Yggdrasil Less Is More?

  1. Yes, please!

    73.8%
  2. Only if there isn't anything else more interesting

    13.6%
  3. No, I would prefer for a loaner an overpriced planar that looks like it's from House Harkonnen

    6.8%
  4. Save up for something better

    5.8%
  1. Beefy

    Beefy Almost "Made"

    Joined:
    Apr 10, 2021
    Likes Received:
    845
    Trophy Points:
    93
    Location:
    Canada
    All talk of warm up times with R-2R DACs......

    I really have a hard time believing the internal temperature changes more than a few degrees, or that it takes many hours for temperatures to stabilise given the small power levels involved. Has anybody taken internal temperature measurements? Or tried expediting the process with a hair dryer or room heater?
     
  2. purr1n

    purr1n Super Friend

    Staff Member Friend BWC
    Joined:
    Sep 24, 2015
    Likes Received:
    75,379
    Trophy Points:
    113
    Location:
    Padre Island CC TX
    @atomicbob had some jitter measurements a while back showing changes over time after turn on. The other aspect is that R2R ladders's accuracy, e.g. INL / DNL exhibits different characteristics at different temperatures (as indicated in the datasheets since this could be a concern for military applications). It may be that the temperature needs to reach equilibrium for the resistor ladder's behavior to settle into something which is consistent. Note that reaching equilibrium <> warm up, although warm-up over time is doing just that.

    The Yggdrasil chassis is pretty big. Coupled with a shunt power supply, which is like leaving a kitchen faucet on all the time so it's more convenient for us to get water, it can get much warmer internally after it gets turned on. There's a reason for all those heatsinks and big ass resistors with a lot of breathing room at the front of the motherboard.

    FWIW, Mike implemented an temperature controlled oven for the GAIN I A-D converter. Maybe's it's voodoo. Lots of things behind good sound are voodoo: shunt regulators, interleaving laminations on transformers, limiting negative feedback, etc.
     
    • Like / Agree Like / Agree x 6
    • List
    Last edited: Sep 21, 2021
  3. Walderstorn

    Walderstorn Friend

    Friend
    Joined:
    Mar 20, 2016
    Likes Received:
    1,246
    Trophy Points:
    93
    Location:
    Europe
    Are your HD800 modded?
     
  4. futbutts

    futbutts Friend

    Friend
    Joined:
    May 15, 2018
    Likes Received:
    311
    Trophy Points:
    53
    Location:
    Shermie Oaks, CA
    Nope. I had the SDR installed for a bit but preferred it vanilla, at least with my pair.
     
    • Like / Agree Like / Agree x 1
    • List
  5. Beefy

    Beefy Almost "Made"

    Joined:
    Apr 10, 2021
    Likes Received:
    845
    Trophy Points:
    93
    Location:
    Canada
    Oh, I'm sure that temperature/warm-up is definitely a factor. It just seems like a really easy thing to test, control for, and modify if someone needs to turn off the DAC to move it from one room to another.

    I'm also starting to think about how different ladder DACs might sound in a Texas summer versus a Winnipeg winter. Even with good HVAC, I'd bet there's a significant difference in ambient temperatures, which would significantly affect internal temperatures.
     
  6. Priidik

    Priidik MOT: Estelon

    Friend BWC
    Joined:
    Sep 27, 2015
    Likes Received:
    1,883
    Trophy Points:
    113
    Location:
    Estonia
    Everything that is not taught in engineering schools and written down into popular books: voodoo.
    Tiny things can make or break the engagement/musicality factor that have no trivial rational explanation behind it.

    ADCs in some top grade multimeters sit in oven, well some of these need to be death grip accurate to 29 bits.
    Makes me wonder what else the oven does to the signal, besides the obvious (music is not that concerned about long time drifts). There is much less all sorts of noise (modulations) for starters.
     
    • Like / Agree Like / Agree x 2
    • List
    Last edited: Sep 21, 2021
  7. GoldenOne

    GoldenOne Friend

    Friend
    Joined:
    Jul 17, 2020
    Likes Received:
    616
    Trophy Points:
    93
    Location:
    England
    I've posted full measurements of the Yggdrasil 'More is Less' version here: https://goldensound.audio/2021/09/21/schiit-yggdrasil-more-is-less-measurements/

    There are some interesting performance quirks to this DAC which likely explain why it doesn't sound as good subjectively as the other versions. It has exceptional performance at 1khz, but the level and characteristics of distortion change both depending on DAC sample rate and the frequency of the signal being played, with higher frequency content having much more distortion.

    It's definitely a really interesting DAC, and I'm looking forward to hopefully listening to it and the LIM version (going to try to see if I can find an OG in the UK too to do all three).
     
    • Like / Agree Like / Agree x 23
    • Epic Epic x 1
    • List
  8. Merrick

    Merrick A lidless ear

    Friend
    Joined:
    Jan 6, 2016
    Likes Received:
    8,789
    Trophy Points:
    113
    Location:
    Portland, OR
    Does that mean one could resample to an optimal rate to get the best sound out of LIM?
     
  9. GoldenOne

    GoldenOne Friend

    Friend
    Joined:
    Jul 17, 2020
    Likes Received:
    616
    Trophy Points:
    93
    Location:
    England
    Using a higher sample rate did seem to help lower distortion in some cases. But 'some' is the key word there. Other situations it just sort of changed it and didn't really 'help'
     
    • Like / Agree Like / Agree x 2
    • List
  10. purr1n

    purr1n Super Friend

    Staff Member Friend BWC
    Joined:
    Sep 24, 2015
    Likes Received:
    75,379
    Trophy Points:
    113
    Location:
    Padre Island CC TX
    Excellent as always.

    FYI: with respect to the ultrasonics (1M bandwidth): the MIL is x4 oversampling, not x8 as is with OG/A2 and LIM. This is certainly very interesting. Looks like a very gentle analog filter was used since the suppression of the beat frequency at 176kHz is -65dbFS relative to the full scale output.
    [​IMG]

    P.S. Feeding the MIL 176kHz and 192kHz data would likely bypass the megacomboburritofilter since this is a x4 oversampling DAC. That could be an possible explanation for the differences between measurements below 176/192 and those at this sampling rate.

    The distortion rising with frequency is odd. Good catch.
     
    • Like / Agree Like / Agree x 3
    • List
    Last edited: Sep 21, 2021
  11. Azimuth

    Azimuth FKA rtaylor76, Friend

    Friend
    Joined:
    Nov 9, 2015
    Likes Received:
    4,332
    Trophy Points:
    113
    Location:
    Nashville, TN
    Home Page:
    • Epic Epic x 6
    • Like / Agree Like / Agree x 4
    • List
  12. haywood

    haywood Friend

    Friend
    Joined:
    Oct 22, 2015
    Likes Received:
    656
    Trophy Points:
    93
    The difference between 17.5khz and 18khz with external resampling in your tests is really odd. And the difference in results between just the megacomboburrito and the dac fed 176.4/192k makes me wonder what the results would be when feeding different sample rates to other Yggys.

    If the increased noise with frequency is due to sample and hold as you surmise though it’s no wonder Mike said it sounds like ass.
     
    • Like / Agree Like / Agree x 2
    • List
  13. Andre Y

    Andre Y Friend

    Friend
    Joined:
    Oct 4, 2015
    Likes Received:
    220
    Trophy Points:
    43
    Location:
    Southern California
    re. Goldensound's MIL measurements, the 1st harmonic for 10kHz is 20kHz, which is already beyond most people's hearing, so THD+N at 10kHz and higher may be audibly meaningless to most people. One interesting possibility are non-linearities folding these suprasonic signals down to the audible range: if you have something that distorts downstream of the DAC, it could modulate these distortion products down into the audible range (cf. IM distortion). I don't think this latter case is what's happening in these measurements, which seem to be more related to aliasing in the digital domain.

    The other thing that's interesting to consider is that when Benchmark made their first DAC, they found that the DAC chip they used performed best in terms of objective performance at 110 kHz, so they resampled all input sample rates to 110 kHz. Apparently at the time, many 192k-capable DAC chips weren't very good up at 192kHz, perhaps due to diminishing filter performance at higher sample rates: constrained silicon budget for filter DSP was/is a real thing.

    The other difference is that 192kHz has a wider passband than 44.1kHz, so aliasing folding down high frequencies causing the extra spikes could be less dense, which could also explain why the distribution of the spikes are different. It depends on what's causing the distortion.
     
  14. purr1n

    purr1n Super Friend

    Staff Member Friend BWC
    Joined:
    Sep 24, 2015
    Likes Received:
    75,379
    Trophy Points:
    113
    Location:
    Padre Island CC TX
    Here are the LIM results to compare apples-apples (except perhaps I did 32k window size for FFT and average of 20). Similar behavior, but a bit cleaner. Cleaner probably because x8. Could these be artifacts of the digital filter processing?

    17.5kHz 44.1kHz
    upload_2021-9-21_17-29-43.png

    18kHz 44.1kHz
    upload_2021-9-21_17-30-41.png

    18kHz 192kHz
    upload_2021-9-21_17-31-37.png
     
  15. purr1n

    purr1n Super Friend

    Staff Member Friend BWC
    Joined:
    Sep 24, 2015
    Likes Received:
    75,379
    Trophy Points:
    113
    Location:
    Padre Island CC TX
    Another look at 17.5kHz 44.1kHz, but this time not at 0dbFS but at -40dbFS (Note that a 0dbFS 17.5kHz would offer no more room for any other signal, also there's very little content near 20kHz).

    Less is More
    17.5kHz 44.1kHz -40dbFS
    upload_2021-9-21_17-42-57.png
     
  16. purr1n

    purr1n Super Friend

    Staff Member Friend BWC
    Joined:
    Sep 24, 2015
    Likes Received:
    75,379
    Trophy Points:
    113
    Location:
    Padre Island CC TX
    Well, yes and no. We can argue that @GoldenOne's 10kHz THD+N and THD+N vs. Frequency plots should be band passed with a 20kHz upper limit because we cannot hear past 20kHz. And indeed this is what ASR does with their measurements, including their SINAD, or what should be better termed as Amir-NADS.

    On the other hand, we if apply a 20kHz low-pass filter, sometimes we see the THD+N line drop off like a cliff once we just get past 10kHz. Does this make sense? If you ask audio gear designers (the real ones, not ones who copy from datasheet recipes using opamps), they will say that the ultrasonics do matter - for reasons what you mentioned (IMD, aliasing, etc.) When I worked with Craig at EC, you can bet that he cared a ton about how the output transformers that he used performed at 50-60kHz. Some transformers had a small ultrasonic peak and he disliked the sound of them.

    Take for instance the ELAC monitor that ASR reviewed. Probably one the best objective results, yet Amir said he couldn't give it a glowing recommendation because the highs sounded off. Guess why? Metal tweeter. I bet that tweeter has a spike at 23kHz or 28kHz - past what's typically measured. Same thing goes for Focal tweeters and Focal metal headphones. Some people really dislike the Focal timbre. There's nothing to indicate weirdness in the audio band with this stuff, but there's plenty above it.

    There's still a lot we don't know about measurements and how they correlate to the senses. There stuff past what we can hear that actually does matter in specific ways and there's stuff that seems it should matter but really doesn't as much as we think (the latter basically being most of misinterpretations at ASR).
     
    • Like / Agree Like / Agree x 5
    • List
    Last edited: Sep 21, 2021
  17. Josh83

    Josh83 Friend

    Friend
    Joined:
    Mar 1, 2017
    Likes Received:
    1,173
    Trophy Points:
    93
    Location:
    Charlottesville
    • Like / Agree Like / Agree x 3
    • List
  18. purr1n

    purr1n Super Friend

    Staff Member Friend BWC
    Joined:
    Sep 24, 2015
    Likes Received:
    75,379
    Trophy Points:
    113
    Location:
    Padre Island CC TX
    It's starts from Muddy Waters. You can generally tell from listening to them.
     
  19. GoldenOne

    GoldenOne Friend

    Friend
    Joined:
    Jul 17, 2020
    Likes Received:
    616
    Trophy Points:
    93
    Location:
    England
    That's a good point actually. I didn't test at lower levels.

    Do you still see the same changes when going from 44.1khz to 192khz? Or when using a 17.5khz vs 18khz signal?
     
  20. purr1n

    purr1n Super Friend

    Staff Member Friend BWC
    Joined:
    Sep 24, 2015
    Likes Received:
    75,379
    Trophy Points:
    113
    Location:
    Padre Island CC TX
    18kHz at 44.kHz -40dbFS
    upload_2021-9-21_18-58-56.png

    18kHz at 192kHz -40dbFS
    upload_2021-9-21_18-59-37.png

    17.5kHz at 192kHz -40dbFS
    upload_2021-9-21_19-0-27.png

    Pretty sure A2/OG does similar stuff. Everything points to their custom digital filter. Probably small discrete errors here or there because it's closed form math. I don't think Mike cares about spurs 100db down or even 90db down for that matter. As long as stuff measures good enough and doesn't "sound like ass", then he's happy. Mike's actually more interested in transient behavior only -60db down (as I am); however this is a wholly different field that will require research and advanced math - with no money in it.

    I once asked him about the absolutely polarity button on the DAC with respect to soundstage. His answer was to use the one that doesn't sound like ass, or I think it was rather "one sounds like ass, the other doesn't." FWIW, people can actually tell the difference with polarity. In theory, we shouldn't right? https://www.superbestaudiofriends.org/index.php?threads/absolute-polarity-test.10019/
     
    • Like / Agree Like / Agree x 1
    • List
    Last edited: Sep 21, 2021

Share This Page