Sonnet Pasithea DAC Review and Measurements

Discussion in 'Digital: DACs, USB converters, decrapifiers' started by purr1n, Jun 17, 2022.

  1. purr1n

    purr1n Desire for betterer is endless.

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    So I was thinking about putting this DAC on the APx555, doing an SINAD panel, posting some THDN and IMD sweeps, cranking the up volume, proclaiming I hear distortion, posting a vote for how I should my Pyrate Skull figure, and then calling it a day for my "review". Except I would be a complete total asshole if I did this. I just can't see anyone who would do such a thing and call it a review. :)

    DSCF0154.JPG

    I've had the Pasithea for about a week now, listening to it here and there, comparing to other DACs, comparing to my vinyl rig, letting it warm up. @GanGreinke was kind enough to loan this DAC to me. He uses it with the EC Aficionado, runs i2s from a Xingxer SU-6 DDC, and runs upscaling software. I think @GanGreinke was using the Yggdrasil A2 with the EC Aficionado which I personally don't think would be a good combination. As the Aficionado can be dry sounding, it pairs better with richer, lusher, smoother sounding DACs. I think it's important for readers to understand that my set up is different and that any serious listening is from my record player through speakers.

    DSCF0155.JPG

    I was hoping to use i2s, but found out I couldn't because the Pi2AES only supports diff i2s via HDMI. The Pasithra takes SE i2s into an RJ-45 jack. I ended up using SPDIF via AES and coaxial. I'm not sure if there was difference between either. @GanGreinke said I could be brutally honest and that he wouldn't be offended if I didn't like it. That takes a lot of pressure off. I hated the Sonnet Morpheus, more than I indicated (I pulled a lot of punches) in my review. The Parsithea however, I don't hate. It largely addresses the shortcomings of the Morpheus to the point where I consider it a good DAC. Would I recommend it? That depends. I do think it's important for readers to understand that I dislike NOS DACs. That doesn't mean that I can't write about them and perhaps give readers a perspective to triangulate or recalibrate their to their own tastes. I feel SBAF has reached a point to where gear discussion is beyond ego. Personally, I love, I relish it, when other people provide counterpoints*, because this provides a more complete picture. I don't know about you guys, I would hope the same.

    To be continued... (I'm tired from planning an audio show and need to take a quick nap)

    *Like well written cogent counterpoints, not "this is da bestest and it sounds bad because the rest of your gear is bad" like this.
     
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    Last edited: Jun 19, 2022
  2. Erroneous

    Erroneous Friend

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    For what it's worth, I think the Pasithea is very source-dependent. I didn't like it from Pi2AES, but @noisyscott and @famish99 really liked it from the Hydra-Z, and we all seem to have similar preferences. So it's entirely possible that what @GanGreinke hears will be way better than what you're hearing.
     
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  3. purr1n

    purr1n Desire for betterer is endless.

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    How can I get a Hydra-Z in the US? Also, will I need the better power supply with the Hydra Z?

    Otherwise the Singxer with i2s seems interesting. i2s does wonders usually or at least incrementally betters the sound.

    We have some budget now with a uptick in contributions. Perhaps a higher-end source for the loaner program would be warranted.

    I have this DAC for a while so I can try other sources. Will continue with the review, but plan for a section toward the end where different sources are evaluated.

    TBH, I don't think a different source will "correct" the main issues I have with this DAC.
     
    Last edited: Jun 17, 2022
  4. Erroneous

    Erroneous Friend

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    I have a Hydra-Z I can loan you, and I have the Allo Shanti power supply too. I just didn't have them when I had the Pasithea in house.
    Not a permanent solution for you, but the offer is there. You can just bring it to the meet to return it.

    And at the end of the day it's still a NOS so if you don't like NOS then you may not like it no matter what, as you said. PM me if you want me to ship these to you.
     
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  5. purr1n

    purr1n Desire for betterer is endless.

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    Will do, maybe bring to the meet. Seems product is discontinued which of course serves readers interested in this DAC no good. However, if the SU-6 can keep up with the the Hydra-Z, having the Hydra-Z can be a good reference point.

    Forgive me if I sound slightly annoyed. Digital frustrates me in such way where I want to run straight back to vinyl. Yeah sure, just as bad with $2k, $4k, $8k tonearms and $1k, $2k, $4k carts, but at least those who are experienced can rely on intuition to get where they want to go. Sometimes digital seems like an endless money pit crapshoot, always needing a Sword of Gryffindor to optimize.
     
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  6. famish99

    famish99 Friend

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    @gridmaster has tested a few in production DDCs that are comparable to the Hydra-Z; I would add that the SU-6 wasn't comparable when I used it.

    I'd say my like of the Pasithea definitely has lots of caveats, namely that I only preferred it to the Wavedream when we were running oversampling via Roon, but it did give it a grand sense of space that NOS usually lacks but also having a thickness in the mids that the Wavedream lacks.
     
  7. rhythmdevils

    rhythmdevils MOT: rhythmdevils audio

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    If you're going to buy a USB source, I would recommend looking into this one. Holo Audio is all about USB with their DAC's and the owner recommends this Intonna unit. Plus, its still in production. He also recommends their USB cables as they state the performance specs on the site.

    https://www.kitsunehifi.com/product/intona-high-speed-usb-3-0-2-0-isolator-1kv-and-5-0kv-models/

    It's also on sale right now.

    I will reach out to Holo, as we were talking about doing a loaner tour with one of these, maybe he would send you one.
     
  8. purr1n

    purr1n Desire for betterer is endless.

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    The two main issues with the older Morpheus DAC (other than it's NOS) were as follows: 1) murky rubbery bass and 2) dull boring presentation. As with all NOS DACs, for those who are not familar, I advise some caution. Even @Hands, who wrote a beautiful NOS DAC guide (now out of date), advises this. Don't jump in unless you are well versed!

    The Pasithea has corrected the the issues I had with the Morpheus. I wouldn't call this DAC dull or boring. Neither is the bass murky. The Pasithea shifts these traits into zones where I find acceptable. Instead of dull and boring, we have polite, forgiving, and pleasant. Instead of murky and congested, we have rounded.

    I wish I had an old Metrum Psvane lying around for a direct comparison to see how the Pasithea has closed the gap with respect to these traits. I'm feeling, it's close but not quite. Heck, I don't even remember the lower mid-line Metrum Ameythst sounding this polite! What I need to accept perhaps is that the Sonnet DACs are just different beasts from the Metrums. There's one thing @Hands remarked that unnerves me: we gotta pay for Metrum (now Sonnet) stuff. To be honest, I would be pissed off to pay yet another $3200 on top of the $3200 (Morpheus) to get sound that I don't consider broken.

    That's an isolator. We need specialized USB to SPDIF or streamer SPDIF solutions. Do you mean to say one of these: https://www.kitsunehifi.com/product/ktesu2/

    To be continued.
     
    Last edited: Jun 17, 2022
  9. Clemmaster

    Clemmaster Friend

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    Don’t you have the Offramp 5 anymore?
     
  10. rhythmdevils

    rhythmdevils MOT: rhythmdevils audio

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    Ahh ok I misread, never mind.
     
  11. purr1n

    purr1n Desire for betterer is endless.

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    You know me. I fucking swore off this shit long time ago.

    Stopped really caring about that much about optimizing digital after I got back into vinyl. And especially after we had Rednet, Rednecks, Mutec, Intona, Wyrd, Regen digital USB de-fuckifier / DDC (digital digital converter) chains. I'd almost want to get a spinal tap than see these chains again.

    Oh no. You simply proved my point! Optimizing digital is awfully confusing.
     
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  12. purr1n

    purr1n Desire for betterer is endless.

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    This is mainly my take. That the Pasithea is a conditional DAC.

    The Pasithea's strength is in the mids and especially with vocals. Thickness is one way to describe it, but it's more than this. Thickness to me is usually an overt qualitity which could be undesirable. But OMFG, how the Pasithsea rendered vocals is nothing short of amazing. Words like full-bodied, inner warmth, lush. Words cannot do it justice. Lots of smiles from family members when they hear human voice singing songs from this DAC.

    The timing of the Pasithea is providential because of the direction, the complementary set up, which I recently put into place for my turntable: a heavy mass Ikeda tonearm combined with a low-compliance cartridge. So I totally get what this DAC is trying to do! 100% get it!

    I mean it's the same thing the Metrums have been trying to do ever since I first heard the Quad and the Hex. Except the Pasithea pulls this off, this midrange "magic", better than any DAC I've heard yet (and like you, this includes the Rockna). I ran Adele, Annie Lennox, Peter Gabriel and enjoyed every second listening to them sing. The Pasithea gets all so close to the Ikeda IT-345 / DL103 in this specific particular quality. This is high-praise from me indeed. (There are some minor niggles which I feel can be corrected with additional dollar-average-to-zero investment with DDCs).

    Now it is fair that I compare DACs to vinyl? Am I sounding like an elitist vinylhead jackass for doing so? The fact is I loved the Rockna Wavedream so much was precisely because it was the DAC that sounded most my like Classic 4 with the medium-light mass VPI 12" metal arm).

    The problem with the Pasithea is that this midrange magic comes at a price: everything is forced through rose colored glasses. It's a bit of one trick pony. More on this later, and with metaphor to turntable setups.

    To be continued, getting sushi from 89 year old sushi Jedi in Corpus.
     
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  13. earnmyturns

    earnmyturns Smartest friend

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    Just to clarify the options: I've owned Metrum Onyx and Sonnet Morpheus, I didn't care for their USB inputs and I ran them with I2S, either via DDCs or Pi2AES. Holo May (and maybe Spring 3) USB is a different story, a small USB source + Intona does IMO an excellent job with it (I should try without the Intona as well in some kind of blind test to determine whether I really need the Intona, but life is too short...).
     
  14. 9suns

    9suns [insert unearned title here]

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    What about trying to get a Sonnet Hermes? It is the matching DDC for Pasithea and has the necessary RJ45 I2S input, which would be synergy and performance "as the manufacturer intended" without any possible doubt or caveat about it.
    It is more expensive than the Singxer or the discontinued Audiobyte Hydra Z, but those don't have the RJ45 I2S input and are not from the same manufacturer, the Hermes would be a nicer addition to the review IMHO.
     
  15. Clemmaster

    Clemmaster Friend

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    In the meantime, you can get the RJ45 I2S adapter for the Pi2AES. Or build your own with a RJ45 cable and crimping tools.
     
  16. purr1n

    purr1n Desire for betterer is endless.

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    @sheldaze has an pi2AES with RJ45 i2s. I'm will be on vacation and be back on July 1 so won't get it to it soon.
     
  17. EagleWings

    EagleWings Friend

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    I have been following the DDC journey of a few folks this past year. AES or Coax out of a good DDC trumps the I2S of a meh DDC. Hydra Z won the heart of literally every friend of mine who tried it. Not because it is a giant killer, but more so that it does its job with almost no sins. AudioGD DI20HE used to be FOTM a while back and still might be in some circles. Apparently this one is legit, as long as you are okay with the large size and the fact it is from the house, AudioGD. Gustard U18 is the current FOTM DDC on head-fi and a few other forums. Ppl I trust say it's up there in terms of performance for the price. But unlike the Hydra Z or the DI20HE, it isn't completely free sins in the treble. Singxer and Matrix DDCs seem to be a step down from the Gustard. Then there are the DDCs from Denafrips, I don't have many data points on these.
     
  18. purr1n

    purr1n Desire for betterer is endless.

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    So anyway, I lied. I have heard other DACs which did similar magic to the mids and human voice. This was so far in the past that I had forgotten. The MSB Analog. I was very tempted to buy this DAC many years ago, especially with the Powerbase. Another DAC that may have gotten close was the AG-D Masturbator something with x8 PCM1704 with a speshal custom HDMI i2s interface via the Off-Ramp 5 USB to i2s converter. The Off-Ramp 5 had some upgrades, but it didn't have the Dual Turbo-Clock which I felt made the sound worse, i.e. moar faster transients. The above setup got smoked, or at least beat in most sonic parameters, for that kind of sound, by an ancient Sonic Frontiers SFD-1 with a CD transport. That's when I gave up DDCs.

    Anyway, regarding my experience with the Off-Ramp 5, special custom made HDMI interfaces, dip-switches on the AG-D for NOS, x2, x4: I guess it was plenty of fun? Not really. It's gives me PTSD flashbacks. It one of those things that you think is fun at the time. Like finding that special rare weapon or armor in World of Warcraft, and then gathering the materials to enchant it for moar damage, moar hit points, moar intellegence. Only that in another year, there's the expansion pack. New gear, newer upgrades, betterer moar damage, moar details, etc. The difference is the WoW is a time-sink. Audio gear is money-sink. Both do wonders (sarcasm) for family life if you have a family. Anyway, thanks @Clemmaster for these old memories and PTSD flashbacks.

    I'll now get directly to why the Sonnet Pasithea is a conditional DAC. By conditional DAC this is what I mean: it's less that it needs special DDCs to get the best of out it (evidently one or more of the following: OOP, under development, costs another $1k-$2k, requires years of due diligence for best synergy). What I mean is that I can't see the Pasithea as the one single DAC in my system. This DAC does one thing very well. But there's a price to pay for this. Many other aspects of sound reproduction while not bad, are merely "good" - where upper-low and mid-tier DACs do them better. This goes with the observation that many have made on SBAF: with some exceptions, paying more than $1500-$2500 doesn't get us better, it gets us different.
    • Transients: Acceptable but still too rounded. We're talking about plucks of the guitar string. Take the beginning of Adele's cover of Lovesong. The attack of the plucked strings is muted, blunted. Again, it's those rose colored glasses at work.
    • Microdynamics / microdetail: I can take the Burl B2, ERC-4, Yggydrasil LIM, Convert-2. Heck, whatever other mid-fi DACs, and they aren't going to smear those small inflections, those instanteous volume changes, the "smoke", and even the strain from Adele's voice when she hits those cresendoing high notes in the chorus toward the end of the song. While the Parthia renders her voice with a beautiful lushness, it subtracts from the reality to accomplish this. There's some inner detail missing here.
    • Macrodynamics: Overall explosiveness. Adele's Don't You Remember starts off gently, her voice backed up with slow arpeggios on the guitar. After the first verse into the pre-chorus, the song then opens up with a huge hit on the tom followed by another huge kick on the bass drum to start the next bar with high-hat quarters, guitar chords eighths, and a corresponding increase in the volume of Adele's voice. With other mid-fi DACs, there's a huge change in volume. The Pasithea stays reticent.
    • Slam: Well more precisely, mushy drums. This was the first track that I heard while the Pasithea was cold and it was not good. (FWIW, the Pasithea needs somewhere between one to five days of warmup. I'm not sure because I did most of my listening before one and after five days). Although this mushiness or congestion does get better, it never quite goes away. The beat at the start of Adelete's Rumor Has It, the thump thump thump thump-thump on the two toms and kick drums is kind of a let down. Not only is the overall volume level muted but the attacks are soft. It doesn't sound anything like kick drums or toms. Could this be possible because I'm running 6" wide-bander back loaded horns instead of the big 3-ways with the 15" woofers? Nope, because the other mid-fi DACs don't do this.*
    Now to put things in perspective, are these shortcomings truly this evident? I am super nitpicking on things that would otherwise not be noticable unless one looked for them. Or I am stating things which are super obvious? The answer is that it's somewhere in middle and that this is below my expectations for a high dollar item, especially a high-dollar item with uninspiring aesthetics.

    Getting back to where the Sonnet Pasethea belongs. It would be great to have a secondary DAC. Or perhaps primary DAC if one loves what it does well and can overlook areas where it does not excel. Think of it like a Grado or HD800. I love Grados, but I would never have one as my only headphone. Heck, I think people have the HD800 as their primary headphone.

    * I hate to do this, because you know how poopy-pants audiophiles love to say how they had a musician say this and that or that they have Stradivarius violins in every home of the block they live on, and this is their opinion and thus they are right. I know how drums are supposed to sound like. Like really know. (My daughter's the drummer, I just tune them.) So I'm right.
    PXL_20220618_142619941.jpg

    To be continued after breakfast. I'll follow up with notes on the NOS soundstage, NOS rolloff, and wax philosophical comparing to the vinyl experience.
     
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  19. purr1n

    purr1n Desire for betterer is endless.

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    I don't think most people will be too surprised when I mention the NOS characteristics of the Pasithea. I don't think I will bother with upsampling software because it's too much of a PIA. I'm ten times more inclinded to physically make another tonearm board. This means measuring, cutting, drilling, fitting, measuring, sanding, finishing, sanding, and finishing another different piece of wood. I hate dealing with computers, software, and settings. Anyone who asks me for this kind of help at work (can you help me find Forticlient version 6.2132, what's the gateway, do I click SSO, etc.), I immediately tell them to call the helpdesk, or say "pretend that I'm dead, what would you do if I am dead" and hang up on them.

    I maded that armboard we see below. I think it looks sexy. Takes me some time, but physical work soothes my soul. Keyboard, downloading software, and futzing around with bad UIs makes me angry. HQPlayer should be implemented as an API or plug-in for Roon. What kind of fucktard developer sells a product for $250 with a clunky shit UI interface.
    PXL_20220618_173300042.jpg

    The Pasithea exhibits high-end rolloff like other NOS DACs. Tonally, it's similar to the Yggdrasil LIM, except the top octave air is non-existent. It's muted too much for my 50+ year old ears to detect. The LIM is laid-back, but it's not totally rolled at the very top. Timbrally, the Pasithea is less grainy, less lush, but we already know that. No warmpoo on Pasithea - excellent.

    Now the soundstage is interesting. I didn't pay as much notice to the Morpheus's soundstage as much before, but this time around I paid much more attention to the Pasithea's soundstage. In the overall scheme for NOS DAC, I found the Pasithea's soundstage confused.

    Most NOS DACs will have a shallow stage, varying width, and a spherical field representing each instrument on the stage with good left to right localization and strong center. The Holo Spring Level 3 did this. The Terminator (in "NOS" mode) did this. It was hard to break the "centering" with these DACs, that is create a hole-in the middle effect.

    This was not the same with the Pasithea. In one very good respect, the Pasithea offered a soundstage that was more expansive, having some depth actually. But this came at the cost of precision localization of instruments and shift of the placement of instruments on the stage toward the edges. There wasn't so much as a hole in-the-middle effect, but rather a double-image effect where a slight shift of my head would result in Adele's voice appearing strongly in two spots, at one speaker, and in the center, and then less present ghost images in several spots between that speaker and center.

    There's a good argument that I'm getting this confused soundstate because my current speakers beam, which they do. However, this does not explain why this didn't happen with other NOS DACs or with any of the arm/needle combos on my turntable. Heck, mono records especially exhibited a stable strong center image which was next to impossible to break even if seated quite a bit off center on the couch.

    Now what I'm going to say next may not be fair. I mentioned prior that the Pasithea rendering of the mids was very much alike that of the Ikeda IT-345 / DL103 tonearm/cart. The exception is that the IT-345 / DL103 doesn't blow it or make compromises in any other aspects of reproduction. The IT-345 / DL103 may be a different flavor from the VPI JMW-12 metal / Cadenza Bronze. Maybe the detail from the conical needle on the DL103 isn't as in our faces, the extremes of the DL-103 are just slightly rolled, the slam and heft are greater from the heavy arm and the medium mass is more flowy. The fact is that both arms/carts don't really sound that different from each other on an external outer level. Their differences are internal, more sublime. And ultimately, they both sound fundamentally correct. I don't feel the IT-345 / DL103 forces music through a rose colored lens. It's more like the difference with film: Velvia 50 slide to Kodak Gold 100 negative.

    So this is why I'm so frustrated with digital.

    It's very hard to emulate what we can do with vinyl playback: that is having different setups that are in a "different" or "interesting" direction while maintaining essentially a correct sound, that is one that is within reasonable bounds. Also, because there is a wealth of collective knowledge and history with products which have stood the test of time (decades) and vinyl playback is physical, it's easier for one to intuitively grasp the effects of doodads. I don't like the idea of spending money on digital doodads where I have no clue as to the effects, or being disturbed that I missed out of the best DDC ever with the Hydra-Z no longer being available. I don't have time trying to chase down the Sword of Gryffindor or the Sword of Night and Flame to slay the digital Vortemort or digital dragon.

    I'll take physical suffering over psychogical suffering any day; which reminds me, I'm heading out to get a deep-tissue massage (pull ups wreck back muscles when you get past 50).

    P.S.

    As far as "freakshow", mono records (with a real mono cart) >>> NOS. Obviously much much much more limited music selection, but if you love music from the Eisenhower era like I do, it's pure win. Mono records are surprising with how they can capture depth and ambient cues. Not stereo, so grooves are only in one dimension, but very pure form of physical media representing sound waves, especially with mono cart made to do only this thing.

    To be continued - measurements tonight.
     
    Last edited: Jun 19, 2022
  20. purr1n

    purr1n Desire for betterer is endless.

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    Measurements...

    Sonnet Pasithea
    Balanced Output, Coaxial SPDIF In
    0dbFS 1kHz Sine, 48kHz sampling rate, 200kohm load
    upload_2022-6-19_21-27-8.png
    panel.jpg

    Note: All harmonics are below -100dbFS. Note that output is on the low side at about 1.5Vrms. SINAD is low because I'm using 90kHz bandwidth. If I lower the bandwidth of the analyzer to 20kHz, SINAD is a very respectable 95db.
    upload_2022-6-19_21-44-57.png

    Same stimulus signal below, but this time 1MHz bandwidth on the analyzer and linear instead of log scale on x-axis.
    upload_2022-6-19_21-31-48.png
    upload_2022-6-19_21-35-38.png

    Doesn't look like there is an analog reconstruction filter. We can see the stair-steps. Let's further confirm a signal stimulus closer to Nyquist: 15kHz

    Sonnet Pasithea
    Balanced Output, Coaxial SPDIF In
    0dbFS 15kHz Sine, 48kHz sampling rate, 200kohm load, 90kHz bandwidth

    upload_2022-6-19_22-13-1.png
    upload_2022-6-19_22-2-55.png

    Instead of a smooth 15kHz signal, we see aliasing because there is no reconstruction filter. In reality, this aliasing is much less worse than it looks. Downstream components are likely to be bandwidth limited especially at the transducer level. Let's see what happens when I ask the analyzer to limit the bandwidth to 20kHz.

    upload_2022-6-19_22-1-21.png
    upload_2022-6-19_22-17-14.png

    Hmm, looks like the aliasing is both better and worse. We are actually seeing a nice 15kHz waveform, but there's more weird stuff folding down into the audible range - the "what the heck is all this other crap"

    Welp! I don't know what's going on. Could this aliasing be responsible for the delightful color, beautiful mids, that we hear with NOS DACs?
     
    Last edited: Jun 19, 2022

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