Delta Sigma: An Inconvenient Truth

Discussion in 'Digital: DACs, USB converters, decrapifiers' started by k4rstar, Jun 21, 2020.

  1. Psalmanazar

    Psalmanazar Most improved member; A+

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    Lo fi gear and processing can be quite universalizing and then probably just the analog stage of the DACs voiced to work with such insane deficiencies. I don’t know why anyone would touch them over Lavry and Burl but that’s me.
     
  2. RedFuneral

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    Pull up any online hearing test. Many NOS DACs continue to push out audible sound when the signal is above the hearing threshold. Even below that level it doesn't always sound as if the frequency is rising as the test goes on. It wouldn't surprise me at all if the NOS tone density worked a bit like how an organ achieves its dense tone, by adding harmonics above AND below the note being played along with whatever distortions/comb filtering you get overlaying the various tones.
    At least that's how I process what's happening & why there is musical satisfaction to be found in it.
     
  3. Hands

    Hands Overzealous Auto Flusher - Measurbator

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    If by "signal path" you expand your perspective scope to the whole chain of DAC-to-ears, Cees (Metrum/Sonnet) has argued exactly that. Between actual LPFs in the upstream gear and bandwidth limitations of gear, drivers, and the human ear, this cumulatively works as a sort of anti-alias or reconstruction filter.

    This is not to say I necessarily buy into that thought. Just adding to what you said by highlighting someone that does in fact argue just that!
     
  4. Hands

    Hands Overzealous Auto Flusher - Measurbator

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    This is almost guaranteed to be IMD in the audible band from aliasing. Sometimes it may just be the inability of NOS to "track" and recreate high frequency signals properly at a given sample rate, but generally it's just aliasing, IMD, and tied to LPFs.

    Another related test is playing fairly loud signals (above -10dB, if not closer to 0dB) above 10KHz on some NOS DACs, especially those with minimal filtering like Metrum. It will sound very weird.

    Thing is, this problem really diminishes outside of static signals and listening tests. Most music isn't going to push much past -10dBFS, especially above 10KHz.

    I've tested NOS DACs that both do and do not exhibit this audible trait in listening and static signal tests. It seems to correlate with whether or not they have rising IMD as the frequency increases.

    What I haven't found is that this necessarily causes much in the way of subjective differences in listening tests between NOS DACs. So, my guess it's not something that generally has much real-world, i.e. music listening, implications.

    I think most of the difference between NOS and OS is due to difficulty NOS has recreating upper frequencies. I don't think it's so much that we hear the actual aliasing or related IMD, but that recreating the music signal will inevitably have a lack of resolution in the high-end in certain cases. Plus the related, slow treble droop this implies is almost guaranteed to have at least a subtle impact on what we hear.

    (When I say we don't hear the actual aliasing, I'd offer up an analogy that we don't necessarily hear a signal the same way we might try to equate that to seeing an aliased image, for example.)
     
  5. purr1n

    purr1n Burned out

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    You have studio mindset, so you don't want the JBL horn supertweeter exploding or anything that could be going into successive input chains to be garbled from aliasing or shelved from high end rolloff. NOS I see as strictly for playback and as @Hands says, for a certain taste.

    These NOS DACs of today sound nothing like the OG CDPs with the brickwall filters. Their sound is intentionally sculpted to sound like that. Take it from someone who owned a first gen Sony CDP (CDP-30), NOS, brick-wall filter, and all. I think that CDP still in my parents house. Besides, it's never been Sony's house sound for large digital playback components.
     
    Last edited: Jan 22, 2021
  6. Psalmanazar

    Psalmanazar Most improved member; A+

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    That was an exaggeration. Oh those og, pre Philips and BB, DACs wouldn’t blow shit up. Neither would pre Waves L1 CDs. These NOS DACs are just more bad digital equipment and processing that will eventually damage and blow speakers. Thank ORFAS, Waves, TC Electronics, and Sennheiser for releasing the HD 800 as is for that.
     
    Last edited: Jan 22, 2021
  7. Azteca

    Azteca Friend

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    I don't have a stake in this fight but I've always seen NOS DACs as similar to adding a tube or harmonic exciter or whatever. Frowned upon in audiohpilia these days (generally for good reason) but it's a color thing. I'd say pick an amp or transducer that gets you the FR you want rather than messing with the non-FR [what I consider] defects of NOS. But to each their own. Personally, using Roon let me really appreciate filtering options for redbook in particular.
     
  8. Psalmanazar

    Psalmanazar Most improved member; A+

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    Good tube gear isn’t nearly as colored. Even warm and sizzly tube gear isn’t. This is far beyond sag, upward compression, and harmonic distortion.
     
  9. k4rstar

    k4rstar Britney fan club president

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    by chance I had a weekend to spend with the Theta Gen Va DAC, it came up for sale locally and a matey wanted me to pick it up for him.

    reviewing DACs is hard work. I think even more so than other components, DAC reviews provide the reader with a great divide between expectations and reality. I try to be conscionable about how someone might interpret such a review, and then go off and spend a lot of $$$, and the feeling makes me a bit sick to my stomach, which is why I never wanted to discuss my own DAC when I first started this thread.

    however this is a unique opportunity for me to compare something of a known quantity to my current DAC (abbasaudio DAC2.2SE) and provide some context for why I strongly prefer non-oversampling designs. for context, the Theta DAC sounds a lot like the new generation Gungnir Multibit. if you've heard that DAC, you are unlikely to be surprised by anything in the sonic presentation of the Gen Va.

    I inserted the Theta in my system, using its S/PDIF input from my USB converter and let it warm up for 24 hours, though it may have only needed 2 to sound its best. on my initial listen, I had been driving around the Canadian winter for 4 hours and my ears were tired from listening to the Cardigans on the radio. it was difficult to tell any overt differences between the Theta and Abbas dacs. both seemed dynamic, fairly honest with transients, even handed in tone, and I was pleased that the Theta did not have any distinct tonal color in the presence region like the Yggdrasil A2 or Gungnir Multibit A1.

    knowing my senses were not 100%, I left the Theta with signal running through it (Mingus Ah Um on repeat) and let my ears recover from the abuse of Swedish pop rock. today I returned to the comparison, allowing 20 minute breaks before switching between DACs to avoid muddling my mind. the Theta is a good converter. I would recommend it if you can purchase it for a good price. there is nothing vintage about its sound, except that it has better tonal characteristics than todays plethora of tonally bleached and washed out converters. in terms of stereotypes, the Bifrost 2 with Unison USB (which colors the sound heavily) sounds more 'vintage' with dishonest bloom and thickness.

    while there is nothing to really fault with the Gen Va on a technical level, switching back to my Abbas DAC provided an immediate sense of relief and relaxation. it turns out I have become allergic to the oversampling converter sound, just as I once became allergic to the sound of delta-sigma converters. let us recap the overt differences between the DACs quickly in bullet point form, and then I will expand on the most important difference of all:
    • the Abbas DAC has what I perceive to be more correct tonal balance and proportions. the volume of treble is decreased on the Abbas DAC but I believe it is more honest and cohesive in relation to the rest of the band. the Theta is brighter with more sheen.
    • the Abbas DAC has fuller mids without bloom, mud or artificial thickness. vocals and string instruments gain body and dimension, while appearing flatter and more monitor-like on the Theta
    • the Theta has good bass pitch and definition. by comparison, the Abbas DAC has outstanding bass pitch and definition, and seems to also go a full octave lower in extension. it may come as a shock that the bass on the Abbas DAC can dig to what seems to be subterranean levels given the biases surrounding the topology of the converter, but it's true!
    • the Abbas DAC has a greatly superior sense of timing approaching the ease of what is commonly associated with non-digital playback. silences in the music begin to take on meaning, providing the listener with anticipation and emotion. on the Theta DAC, there is no sound, and then there is sound, and that's it. the imagination is not activated.
    • the Theta DAC initially appears to draw sharper outlines around aural images. this comes at a cost of body and tonal proportion. I prefer the Abbas DAC which is not smeared but neither is it artificially separating elements in the sound scene.
    these overt differences grew larger as I listened to older recordings produced better recording equipment with less heavy-handed studio technique, and the differences grew narrower as I moved to modern remasters, pop/rock productions, etc.

    while the above differences certainly have to do with more than just NOS vs. OS, the greatest difference between the two converters is that the Abbas DAC retains the emotional aesthetic of the music/recording while the Theta DAC discards it. this is not a weakness specific to the Theta but rather all oversampling converters I have heard regardless of price and topology. I have certainly not heard all of them (and I honestly don't plan to listen to any more!), but somehow I do not think spending $5,000+ on an OS DAC will suddenly give you this elusive trait.

    this is the difference between putting on a recording and allowing your subconscious to immediately relax and take in the time and place of the recording, its means of production, and ultimately experience musical ecstasy through conjured emotions. if this sounds like bullshit to you, it's OK, I understand. some will prefer the intellectual masturbation of discussing Nyquist theory, reconstruction filters, pre/post ringing, sin(x)/x loss, blah blah blah blah blah. I don't engage in these discussions because I feel they have very very little to do with how well or not well a component reproduces music. it's something that is felt rather than heard and this is exactly why I started the loaner program for the Abbas DAC. not everyone will get it, but I am very excited for those who do.

    the Theta is still a good DAC, I could have just as easily rewritten the above to make it sound like the best thing since sliced bread. if you want to read a review like that I think there is one on Changstar. I am curious now what can be done with the PCM63 chip operating in NOS. that is all.
     
  10. purr1n

    purr1n Burned out

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    LOL, I should remind you that were were the one who first started on the intellectual masturbation elements on OS, intimating that somehow the math and science of OS was flawed. I suggested the more straightforward approach of simple subjective opinion: I like how this sounds.

    I noticed that Abbas does have a PCM63 version.

    P.S.

    I'm curious if you have heard the Holo Spring DACs. These DACs are NOS (they do have OS mode, but OS mode sounds like shit), but not as warm or full-bodied as most other NOS DACs. In fact, they are closer tonally to the Soekris DACs than the Metrum DACs.
     
    Last edited: Jan 31, 2021
  11. k4rstar

    k4rstar Britney fan club president

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    you're right, mea culpa

    about the Holo DACs:

    [​IMG]

    I have not heard them. my zone of audio influence does not go further east than the ex Soviet bloc. I see a lot of things inside them I make poopoo faces at. better for people who have more faith in Chinese products
     
  12. Psalmanazar

    Psalmanazar Most improved member; A+

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    Eastern Block tube matching...
     
  13. Jh4db536

    Jh4db536 Friend

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    Gamma3 DS DAC, Yggdrasil A1 (GS rom) always using AES
    PI2AES via coax will be used to form these impressions
    I will try my CDT later and maybe update this
    HD600

    **this'll be a stream of consciousness after listening to it for only a short 2 hours. I believe my objectivity and initial gut feelings are best in the beginning before my biases take over. It's been a while since i've played with fresh gear. I'm not going to go into "why" it sounds like this or that. Just what i heard and maybe i'll add in my thoughts about why someone would prefer this type of sound.

    Remarks upon plugging Abbas in is that i hear a very high pitched tone maybe 15-20k Hz in an otherwise black background. Gamma3 and Apple Dong are black black. Yggdrasil has some issues blackground as well but it's not doing any tones. I can only hear the tone on headphones with the volume up. Owner said its sensitive to rF noise. Maybe it's picking up the rF noise from the DHT heaters in my MKIV or all the wifi i got going on from the Pi2AES. It's not detracting from my overall experience so i will move on. Tried it with my AMB M3 amp, and the noise went away so ig it isn't that happy with amps with ultrasonic heaters.

    Not soft and round like metrum DACs yay! Sorry, but that's not my flavor. Does not slam as hard as yggyA1 (Yggdrasil can slam so hard it hurts; even gumbyA1 slams on Marvs 445), i will call it's slam Above Average (probably high compared to other NOS). Like Yggdrasil there's no treble harshness or digitus even on harsh recordings like i get on my Gamma3 (anti clip filter rolls it off to a tolerable level). I think Yggdrasil does extreme highs without rolling it off and with more air and gets an A+, while Abbas gets a A- since it deals with it primarily by rolling/rounding it off. I use Billy Jean, Rock My World to assess slam and hot female vocals like Yao Si Ting to assess the highs. Yggdrasil takes the highs to the absolute limit and that's one of its special qualities, it will even show a little edge without going off the cliff if it's really there in the recording and wont attempt to just hide it while still keeping it tolerable.

    In terms of FR its n shaped (or maybe the mids are just overpowering everything else by a significant amount): Powerful, super sweet, BIG mid focus... Has sparkle, but extreme highs and lows are kinda rolled off slowly (not a cliff). Yggdrasil gets a D for bass quality in my setup because it exacerbates wolly bass at a certain frequency. The bass on the Abbas is maybe a solid B cause the extension and level of roll off isnt that bad. DS DACs like my Gamma3 get an A for bass quality and extension. I am confident my HD600 sounds like a very even FR with my normal setup. Play something like Mick Gordon - BFG edition and it still doesn't sound clean like a good DS dac but its engaging AF.

    Abbas has intimate (NOS) stage or presentation like yggyA1 but way more extreme...in your head basically. Pinpoint focus in the center of your head. This doesnt bother me with headphones, otherwise i would have a gumbya2 instead of an Yggdrasil. The Coherence and immediacy probably makes many other DACs sound distant, veiled and thin. The Abbas has Coherency trading off for the separated exploded view like the Yggdrasil, but that's the tradeoff of sweeter more focused mids. This is not about thicc or thin; thicc to me sounds like sonic frontiers ultra analog. I prefer Yggdrasil's superiority here, i can distinctly peel back every layer of the music with Yggdrasil, but this is a appreciated alternative. On something like Smooth Criminal, Abbas sounds like everything is happening on a single powerful coherent layer. With Yggdrasil, you hear every layer distinctly, the heartbeat, the guitar, beat, vocals, samples, cymbals, etc and it varies on its own individual level. These spaces is also where Yggdrasil's "grayness" happens. There is no gray with the Abbas, it's loud and clear right in your face.

    **I must add the separation that i speak of Yggdrasil only happens in Albums that i thought were well recorded. If it doesnt work, it sounds less than spectacular - think Pop and Hiphop genre. I filtered out these from my playlist, put them in a box or i only listen to them through my phone and earpods. Abbas Dac works better for these. Try something like Post Malone on it, sounds pretty fun.

    Dynamics and minute differences in amplitudes on Abbas not as good as Yggdrasil (Yggdrasil excels at this). I believe Abbas rates poorly in this technicality. The extreme focus in your head plus the actual n shaped mid focus makes everything sound 'uniformly loud or only a few levels of loudness' to me. When i listen to Michael Jackson:Essential MJ things like smooth criminal, beat it, PYT all sound loud when i know they are definitely not with Yggdrasil or even Gamma3. This specific lack of technicality bothers me. I dare use the C word, but you know what i mean. Most pieces of the music are upfront and center and loud with the Abbas; whereas on Yggdrasil they are separated, placed at different distances, and individually doing their own thing. That works for certain genres of music and might not be everyone's preference.

    Gamma3 is Wolfson based DS and has superior blackness, bass, huge stage, air, width, depth, technical objective measurements. It has treble stridency which can be mostly rolled off using the anti clip. I think it even outresolves my Yggdrasil. It's main sin to me is its boring and Bleached after a while...not fun even if it had Yggdrasil perfect trebler. it's just too filtered and cleaned out to the point of this thread. like a pretty grill that's boring AF

    Compare that to good Vinyl, where the goodness is already there and it's about improving its technicalities, lowering noise floor, etc.

    Conclusion and on subjectivity:

    The Abbas is a very FUN and engaging dac on headphones IMO...more fun than Yggdrasil if you wanna dial back the technicalities further and get more than "just noise coming outta a driver". I view Yggdrasil as my Fun Dac, she's pretty enough and will get down n dirty. If i wanted a totally technical dac i would just use my Gamma3. There's always tradeoffs and you have to pick your poison carefully and it might change depending on the downstream. With the Abbas you gotta accept some Compression and poor separation as the tradeoff just as you have to accept Yggdrasil's poor bass quality...and remember, that's in the context that im still on the stock output transformers (or maybe it's that cathode bias sound). The warmer a DAC is will exacerbate my perceived bass issue. The Abbas is probably slightly less warm than Yggdrasil and i think Yggdrasil is 1 or 2 click Warm from neutral (or it has some midbass hump like HD650 built in). I think the Gamma3 is neutral. The Theta Gen Va is probably my perfect DAC from what i heard it doesnt have this extra warmth.

    When i listen to female vocal tracks, i barely hear Yggdrasil's bass issues. When i pair this with Techno, Rock, and stuff that i think the owner listens to, i would rather use the Abbas cause Yggdrasil's bass quality sticks out like a sore thumb. Yggdrasil does everything else Right IMO and that's why i haven't changed it as my main DAC. Sometimes when i listen to Rock and Techno i.e. Daft Punk i cant stand the Yggdrasil and use the Gamma3 instead. I think i could prefer the Abbas over the Gamma3 to use for those genres. I dont think changes in amplitudes separations matter that much in like electronica genres anyway. Not all music was meant to be dissected into layers and separated out onto different dishes. Sometimes it just sounds better with the Abbas presentation. Punk rock albums that i used to write off as a shit recording with my regular setup might sound decent with Abbas Dac.

    DACs come in a wide variety of flavors and I am glad i got to experience this one. I would actually prefer this DAC over the Yggdrasil as a Fun-dac if it didnt make everything sound homogenous. I was expecting major roll off at the extremes and softshit but the Abbas didnt disappoint on those qualities. I would love to have one of these around just to listen to pop on spotify or pandora...it does really well with simple music that doesn't have a lot of stuff going on ie. an acapella or solo. Female vocal like the Yao Si Ting stuff sounds really nice on this DAC, that's where the emotional stuff is translated ig. Orchestra, classical, some jazz, complex stuff skip it.


    [​IMG]

    Update: I have an assortment of 6922 type toobs around that i use as drivers in my other amp. I think now that the loaner included philip (large Ogetter) 6922 is partly responsible for the powerful mid intensity. With something like the golden lion 6922 the FR is much more even but loses the sweetness/wetness (very dry sounding), slam, fun. I didn't like Siemens in this DAC, it's too extreme too exaggerated. My philips (small OGetter) sounded similar to the "miniwatts". None of this stuff can 'correct' the underlying NOS sound. Philips tube for 'Fun', golden lion if you want it to sound more normal and boring. I'm sticking with the philips and i believe it is the right tube for this particular DAC.
    [​IMG]

    Update: All my impressions above are with HD600 and the intensity level is super high. I brought out the HD800 for the hell of it and it is an interesting pairing if you need more "space" in your head or if you need to tone down the level of intensity. You can really tell how good the mids on the HD6xx series are though after switching because this DAC puts it to full use.
     
    Last edited: Feb 26, 2021
  14. loadexfa

    loadexfa Friend

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    Some brief loaner thoughts. Something to note, DACs are the most difficult for me to hear differences and express what I'm hearing or why I like something or not. Much more subtle that transducers or amps. I've been trying to find the right synergy for me with the Stratus and ZMF/Sennheiser/Focal. I think the A2 Gungnir is a little too dry and possibly cool. The Pavane is not quite "there", not sure why.

    I found the Abbas DAC to be thick, rich, and overall a pleasant listen. I can see why k4rstar finds this presentation more emotionally engaging. The Abbas didn't always land that way for me, not to say I disliked it but there was something missing. For classical music it was more obvious, I found the Abbas lacks space and is too thick. In contrast, live folk music was my favorite and I didn't want to stop listening.

    I felt the thickness and tone was good for the HD 800 and was fine with headphones in general though there were times I found it too thick with the Elex.

    The Pavane isn't as thick and has more clarity and space. The Abbas is more slammy and/or hits harder while the Pavane has more extended bass. I found details easier to pick out with the Pavane.

    Overall I liked the Abbas DAC and enjoyed it with everything but classical.

    Thanks @k4rstar for making this available!
     
  15. Jaylat

    Jaylat Rando

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    Here's my review of the abbasaudio DAC0.1 SE

    Office Setup: Sparkler Audio S504 Unison DAC > Belles Aria Integrated > Harbeth P3ESR
    Main: RME DAC > Luxman CL-38 Pre > Luxman MQ-88 Amp > Harbeth 30.1

    [​IMG]

    This is a great sounding DAC, many thanks to @k4rstar for making it available!

    I tried it in both my systems, a tube system (Luxman MQ-88 and CL-38), and a solid-state system (Belles Aria integrated), both with Harbeth speakers. As might be expected it had a more noticeable effect on the Belles Aria, but it sounded very good in both systems. The Abbas brings the same fullness to the music that a good tube set does.

    Listening to it over several days, the Abbas DAC brings a “roundness” to notes and a really palpably rich sound that makes certain instruments like the bassoon or a nice jazz sax really come alive. My current tastes run to Baroque chamber music and bebop jazz, so it’s great for that. Smaller ensembles sounded better than orchestras or big bands, which occasionally came across a bit fuzzy.

    Comparison to my other DACs, a Sparkler Audio S504 Unison DAC, and an RME ADI-2: The Sparkler is a lot like the Abbas as it also uses a Philips TDA1543 chip, and is a unique DAC, hand assembled by the designer. The Sparkler however is a solid-state DAC while the Abbas uses tubes, so a bit of a different approach.

    The Abbas was able to match the Sparkler’s rich sound, but it lost a bit of detail versus the Sparkler. I had it set up in an A-B comparison and even my non-audiophile wife was able to hear the difference. So I prefer the Sparkler, which to me had the ability to match the fullness of sound while still preserving lots of detail. But keep in mind the Sparkler is over 50% more expensive than the Abbas.

    The RME is the polar opposite of the Abbas and Sparkler, a highly complex, professional piece of equipment with tons of bells and whistles and a 72-page manual to figure it all out. The Abbas is definitely richer sounding than the RME, which can sound clinical at times. Again, you can hear lots more detail on the RME. This shootout was more of a toss-up, as the Abbas brings a lot to the table that the RME lacks.

    Honestly all of these are very subtle differences. Very often the choice of speaker or the quality of the original recording end up being much more important than the DAC in determining how the music sounds. At least for me, the choice of DAC, though important, is secondary to these other factors.

    I enjoyed this DAC, thanks again.
     
  16. Claritas

    Claritas Friend

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    Abbas DAC0.1 SE and Yggdrasil A2

    Let me begin by warmly thanking @k4rstar for sharing some of his sonic preferences and gear with me.

    I haven’t yet had the pleasure of reading the opinions of my fellows on this tour because I did not want to be influenced in any way. But now that I’ve had the opportunity to hear an Abbas DAC for myself, I am eager to read of others’ experiences.

    Equipment:

    Denon DCD-1560
    Abbas DAC0.1 SE
    Yggdrasil A2
    Meier Classic (non-FF)
    HD600

    Note: I marked noteworthy pros and cons with a plus or a minus at the start of some paragraphs.

    Abbas DAC0.1 SE:

    + The frequency response is balanced: no undesirable emphases. At most, it’s possible that the midrange below 1kHz is favored slightly.

    Musical texture sounds more uniform than usual. Pronounced shifts in volume don’t stand out. That seems halfway right to me, which is a greater compliment than it seems, because I’ve heard many more DACs that exaggerate this than understate it.

    - The overall presentation approximates the layout of a concert hall as heard from the middle of the orchestra section. It differs, however, in an important respect. The stage depth is compressed, and the result is less three-dimensional. This isn’t true to life. It’s more problematic for orchestral works. The staging is rather flatter, like a painting, but it makes for a very pretty painting.

    In large-scale works, the music is not conventionally layered. Instead, the orchestral sections seem to overlap. That might actually be truer to life, if not more enjoyable.

    Empty space on the stage is an element in projecting an “open” and, thereby, bigger stage. But, here, the empty space on stage sounds filled in: not with sound, but with a slight thickening. This “filled empty space” adds some clarity to the relative position of the instruments to one another. This helps to give the ensemble greater or lesser cohesion, as required by the music. E.g., two violins playing overlapping soli can be easily and clearly distinguished. The overall effect is natural or true to life. Soon I’m no longer thinking about it. That’s a good sign.

    - Very specific effects at low volumes (e.g., a momentary variation in the bass line) barely register. You hear them only if you know they’re there and you’re listening for them.

    - It sometimes struggles or even makes a hash of fast, complex passages. They don’t sound blurry; they sound either strained or sloppy. The problem arises only when many notes are played very fast.

    Quiet, ambient background sounds aren’t brought into the foreground. The result is more true to life, if sometimes less enjoyable.

    + Instruments (for some reason, woodwinds especially) sound very realistic. I cannot emphasize this enough. What’s more: in addition to the notes, you can actually hear the sound of the physical act by the musician—the bowing and plucking of string instruments, the quills plucking the strings in a harpsichord, the depression of the keys on a keyboard, &c.!

    + The final decay at the end of a piece is less abrupt, uniformly fading, which is both more realistic and better-sounding.

    Yggdrasil A2:

    - The extra bass is obtrusive—more than merely noticeable. It’s particularly bothersome in solo instruments, piano most of all.

    - In alto vocals, the higher notes are a little rounded off; maybe slightly closed-in. Likewise, the treble on pipe organs is less incisive than it should be. I don’t think this a case of masking. It simply seems a little too polite.

    The overall presentation is aggressive—“in your face.” This effect cuts both ways: it can be excitingly close, or it can be uncomfortably close. In any case, the presentation is not true to life, to a concert-goer’s experience of live music in a concert hall.

    It makes use of three different capacities to convey a sense of empty space around the performer or ensemble. 1) Emphatic bass lines flow out from below. 2) In orchestral music, it can sound as if the music is not quite in a continuum, and instead leans somewhat in the direction of having distinct stages. 3) It picks up the sounds of echoes buried in the recording fairly readily. Of these, no. 1 has a true claim to accuracy, as when a cello pulses from a stage through a floor of natural wood. Numbers 2 and 3 are contrived, but no. 2 still has some genuine merit. It serves both analytical and musical purposes. It helps one notice the direction of the music (toward crescendo or diminuendo). The score becomes more readily explicable.

    + It’s extremely good at revealing small details. Even when listening to pieces I think I know through and through, I sometimes hear a note or a chord that I simply had never heard before because it had been covered up by a more dominant theme. Musicologists have disagreed about whether this is more realistic or less, but I definitely enjoy it.

    + Individual notes and chords have an unnatural thickness that allows me apprehend them as almost three-dimensional objects. It makes it easier for the listener to pick out lines of counterpoint, and to more easily grasp the structure of that type of music. Undoubtedly this is artificial, caused partly by slower-than-accurate decay. There is nothing like it in live concerts. But it’s still a neat trick! For better and for worse, the fake thickness allows for less-common sound combinations and makes for a broader color palette.

    + It handles fast, complex passages with ease.

    Quiet, ambient background sounds are brought into the foreground. The result is less true to life, if sometimes more enjoyable.

    - Most of the time, individual instruments lack focus. When the strings section plucks a string, I hear what I can interpret as “a string has been plucked” or “string-plucking sound was produced.” But I do not hear the natural sound of the instrument, which leaves a rather negative impression. There’s nothing live about that. Likewise, two violins playing simultaneous soli come out mushed together and indistinguishable, robbed of most of their emotional content and impact.

    The final decay at the end of a piece sounds slightly unnatural. It’s not immediately clear why. Some of the problems or other aspects already mentioned could account for it. On its own, it’s nothing serious.

    Conclusion:

    I enjoyed really very pleasant moments with both DACs. They achieve very different effects. Yggdrasil needs some care when one attempts to find synergies—if one can tolerate the bass. The Abbas, although rather unconventional in what I tend to expect from a DAC, is more versatile because it’s quite balanced, with no particular range overemphasized. Yggdrasil is considerably better for analytical listening. Abbas is truer to the sound of live performance. Both are very good DACs, and the choice between them will depend on one’s preferences and/or needs.

    Thank you for being amongst the people I can discuss these subjects with.
     
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  17. Metro

    Metro Friend

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    But Yggdrasil's closeup presentation may be an accurate representation of the recording, which are usually done with microphones close to the performers. A concert-goer’s listening experience is from a seat out in the concert hall. When I go to symphony concerts, I look at the microphone placements and it's clear that they will capture sound much more closeup than sitting anywhere in the audience, and this must be kept in mind when listening to audio equipment.
     
  18. Jay

    Jay Facebook Friend

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    I came to revelation tonight, which was about 8-9 years in the making. I never claimed I was the sharpest tool in the shed, but eventually things do come to me.

    I've been using the Modius balanced as my primary DAC for several months. I also have the Gungnir MB A1, but I rolled that out of rotation since getting the Modius. Well, lately, the treble from the Modius has really been bothering me. I'm not sure if it's the Velvet sound stuff (I'm running it balanced) or if my ears adjusted, but it has sounded a bit off to me lately, basically unnatural.

    Because of that, I decided to roll my DACs to see if I could tame the treble for a bit. I rolled back in my Gungnir MB A1, and the sweet MB sound brought a smile to face. The treble issues have been resolved a bit and things sounded natural again. Sigh of relief...my ears still work and appear to be healthy.

    But, while I was in the DAC rolling mood, I decided to dust off my Musical Fidelity V-DAC II, which I hadn't listened to in at least 8-9 years. I bought it when I first got into mid-fi computer head-fi audio because the interwebs told me it had a nice sound. At the time, I really liked the V-DAC II and thought it had a nice treble and pretty decent bass slam, all while having just a touch of warmth to it. I never knew much about the actual chip it used, and I never really cared because it was all about the music. Music sounded natural to my ears.

    Anyway, when Schiit first hit the scene, I got sucked down that rabbit hole with Bifrost Uber then Gungnir MB. I fully subscribed to the R2R sound approach is better than DS, especially when it comes to treble, for my ears. The V-DAC II got thrown into a closet and basically forgotten until this weekend. I got really used to the Moffat sound and grew to like it, especially the multibit sound. After switching to Modius for a bit, I had forgotten just how nice the multibit sound is.

    After rolling the V-DAC II back into rotation this weekend, not only did it bring back nice memories of the good sound I enjoyed in the past, I was immediately struck at how nice and balanced it sounded for a mid-fi device. More importantly, the treble was nicely controlled and was better for my ears than what the Modius had been doing lately. Is it Gungnir-level good? Of course not. It was an overall leaner sound to it, but it's also a bit more polite when the Gungnir can be a bit more in your face. While Gungnir is more aggressive, it has more space and air, and the V-DAC II can get a little crowded at times despite being leaner and more polite.

    So....to get the point of this post, I finally did some digging this weekend into the chip that the V-DAC II used, and I found out it's the Burr Brown DSD1792. This is a hybrid chip that combines an R2R ladder and DS modulation. If I read the white pages correctly (I may not be so I'm sure the more skilled people here can correct me), it uses the R2R ladder for the upper 6 (most important) bits and DS for the lower 18 bits. I guess this explains why I always liked the sound of it because it has some elements of R2R in it. Back all those years ago, I was none the wiser, but now things make sense. It also explains why I always thought it sounded better after a few hours of warming up when I could never really discern improvements in DS DACs after about the first 15 minutes after initial power on.

    I wanted to share a little love for the V-DAC II and its DSD 1792 chip. It's not a bad little device and I plan on running it for a while.
     
    Last edited: Apr 12, 2021
  19. crenca

    crenca Friend

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    Just about all (maybe all?) the iFi DACS use the Burr Brown 1793 chips, which is just an iteration of this 1792 if I am not mistaken...Just an FYI if your V-DAC II breaks ;)
     
  20. purr1n

    purr1n Burned out

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    There were a quite a few good DACs back in the day and the reality is that DACs aren't that much different or better. There's a reason why a handful of people here still sport the Sonic Frontiers DACs and why we recently did a blast to the past with the AMB Gamma 2 (https://www.superbestaudiofriends.o...mma-2-dac-or-how-nwavguy-fooled-us-all.10173/)

    Musical Fidelity made a lot of good stuff 10-15 years ago. I don't know if they still do now - would be worth investigating.

    With respect to Modius and the highs, chalk that up to the latest generation AKM chips: some things better and some things worse.

    The first outboard DAC I purchased was a Theta Cobalt 307. It's still a pretty good sounding DAC. I had no idea who Mike Moffat or Jason Stoddard were back then. The Cobalt was the entry level trickle down model from the fancy Theta stuff and it too used a hybrid chip.
     
    Last edited: Apr 12, 2021

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