Review: Holo May (L2) DAC and the Musetec Audio (LKS Audio) MH-DA005 DAC Compaired




Musetec Audio (LKS Audio) MH-DA005 DAC and the Holo May (L2) DAC Compared

A comparison of these two DACs is something I wanted to do for months given the numerous stellar reviews of the May and the widely unknown, but highly praised, 005. Those of us who own the 005 believe it is an undiscovered gem. I bought the 005 initially because it was cheaper (approximately 3K) and because of the wonderful experience I had with it’s predecessor, the 004. After hearing and greatly enjoying the 005, I found it hard to believe any DAC could be significantly better. Eventually my curiosity got the best of me and I had to find out. There were no comparative reviews. After selling some equipment that I wasn’t using for a few thousand dollars, I coughed up the 5K to buy it, thinking I could always sell it if I didn’t love it more than the 005.

After about approximately 500 hours of break in, as recommended by the manufacturer, the May was ready to compare with the 005.

First, before I begin, the reader should know my perspective and preferences. I started out in my teens and early 20s, during the 60s and early 70s, as mostly a rock and roll fan with some rhythm and blues and folk music thrown in. Around 1971 I found a lack of good new rock music (the Beatles broke up, the Stones became inactive, and Dylan had a motorcycle accident). So I tried some classical. At first I found it boring but very gradually over the years I became addicted. When I moved to Manhattan, I went to classical music concerts frequently and eventually subscribed to the New York Philharmonic. I continued my subscription for over 20 years. In addition to orchestral music I attended chamber concerts and some opera.

My perspective favors live natural acoustic music, though I still love classic rock and oldies. To me the preferred audio sound is one that feels like a real event, a live, in the room, palpable presence. Natural resolution and detail is essential. (In physics lingo, my goal is to hear all the overtones, on top of the fundamental sine wave, which define the timbre of a real world instrument or voice.) I seek a sound that is accurate and clear, but slightly warm, conveying rich but realistic lower mid-range and upper bass much like what you would hear in Carnegie Hall or Symphony Hall in Boston.

Many music lovers are not into classical so the music referred to below may be unfamiliar. Nevertheless, the conclusions I’ve made as to sound should have relevance to all genres.

Preliminaries

I fed both dacs via computers (an Asus mini and an Asus laptop) because I had two. Thus I could do quick comparisons by preamp input switching. I recently bought an Ifi Zen Stream network bridge/streamer which, after some frustration, I hooked up via ethernet cable. Since I only had one I could not use it to do quick comparisons between the two DACs.

For the record, the 005 fed by the Zen Stream via usb did improve the sound by lifting a slight veil of haze, which you might not know was present until it was removed. With the May a slight improvement might have also occurred, but the effect was less clear to me, because I didn’t have time to do much listening with and without the network bridge.

Both DACs were played through a Hegel P30 preamp to a McIntosh MC402 amp, then to Kef Reference 1 speakers and two SVS sb-3000 subwoofers crossed over at 46hz.

Method

I began with critical listening focused on sound quality using a/b switching. Generally, I would listen for about a minute or less to one then switch to the other to hear the same passage.

I will report in the future on longer term impressions after living with these DACs for a few weeks.

I started with the following music tracks. I chose them to facilitate focusing on certain sonic elements listed in parenthesis below:

1. Solo piano: Beethoven Appassionata (transient attack and decay, timbre/overtones, micro detail, clarity)
2. Violin Sonata: No 1 Prokofiev (timbre/overtones)
3. Piano trio: Beethoven “Ghost” (imaging)
4. An aria from an Oratorio by Handel entitled Theodora (imaging, female voice, hall ambiance)
5. Large orchestra, soloists, chorus, and massed strings. Mahler Symphony no. 2, final movement. (congestion, hall ambience and depth, width, and imaging)
6. Light My Fire, Doors (energy, rhythm, male voice)
7. Sunshine of My Love, The Cream (drums, energy, rhythm, male voice)

Round 1
The Solo piano test. I choose Beethoven’s Appassionata played by Arthur Rubinstein. I think a solo piano reveals transient speed, attack (leading edge of the note), and decay like no other instrument.

It was almost a tie in these sonic qualities. Both were excellent. The 005 to my ear had slightly better definition and decay. The May had a slightly richer bass tone and was solid and very pleasing. The 005 was leaner but had more sparkle, capturing all the natural overtones on higher notes.

Round 2
Violin Sonata: No 1 Prokofiev performed by Vicktoria Mullova.

The results were similar to the piano test. The 005 clearly had better reproduction of the natural overtones of the violin. The May was bassier, with the music emerging from a blacker background.

Round 3
Beethoven’s “Ghost” Trio for piano violin and cello performed by Istomin, Stern, and Rose.

Imaging was about equal with each instrument appearing in space laterally where it should. The 005 placed the instruments more forward as if your were seated closer to the stage. The blacker background of the May made the separation of the instruments clearer, but the warmth made the musicians seem more recessed, as if your seat was well behind the 005 “seat”. The May sounded slightly soft but was solid, beautiful, and addictive, if not completely convincing on vivid violin timbre.

Round 4

Next, I played an aria from Handel’s Theodora, sung by the late and brilliant mezzo soprano Loraine Hunt Lieberson. It consists of the vocalist supported by a cello and harpsichord (basso continuo). I chose this because the recording contains only two instruments and a singer. It thus presents a good opportunity to clearly hear imaging and hall ambiance in addition to providing a well defined lower midrange and bass line, and a beautiful female voice.

Both the May and the 005 sounded completely convincing and beautiful, especially in realistic tonal balance, including rich bass and a clear cello, harpsichord, and voice. The sound field width had the same realism in both. Loraine’s voice image was more natural in space, clearer, with a touch more air on the 005. The May had a bit less clarity, as it sounded further away, but was a tad smoother in texture.

Round 5
Mahler Symphony no. 2, final movement. Bruno Walter, the New York Philharmonic. A large orchestra and chorus with soloists is a good test of dynamics, detail, sound stage/ability to retrieve hall ambiance, clarity, and imaging.

The two DACs were equal in dynamics but the 005 was superior in every other way. The 005 picked up more air in the hall, exhibited no congestion between instruments, produced a deeper more natural sound stage, not by virtue of more bass, but more air or hall ambiance. In this case better hall ambiance produced more vivid imaging. The 005 was vivid and conveyed more emotion. Chorus voices were not as distinct in the May. Vocal soloists were clearer in the Musetec.

Round 6
Light My Fire, Doors (energy, rhythm, male voice)
Very close in all aspects. The 005 seemed to articulate higher frequencies better and thus had appropriate edginess.

Round 7
Sunshine of My love, The Cream (Drums, energy, rhythm, male voice)
Again, very close in all aspects. I can’t tell the difference.

Conclusion
First and foremost these DACs were both excellent in every category. At times during the A/B listening I could not tell them apart. To be sure, they are different, but if a listener familiar with the sound of both walked into a room without knowing which DAC was playing, it would not be surprising if he or she guessed wrong. The take-away is, in my opinion, they are both in the same class. The point of this exercise though is primarily to determine their differences.

As I said earlier, the live realistic character of the sound wave comes, in large part, from capturing all the overtones. This gives accurate timbre and detail. The 005 has more than the May. Another component of realism, in my opinion, is solidity of texture and prominence of the sound emerging from the background (black or zero background noise). The May has more of this.

In fact, the May’s blacker background is like nothing I’ve ever heard. It has an uncanny realism, solidity, and ease. It sounds like the very best vinyl. Smooth always listenable and engaging. Overall it is sweeter and softer than the Musetec. Probably even more so than actual live music. I call this natural texture, for lack of a better term.

In sum: sound texture May wins; Realistic space, detail, micro dynamics, and high frequency energy, the 005 wins. Clearly the Musetec works best if listening to a large orchestra where details, hall ambience, and clarity (lack of congestion) are priorities.

If the price were the same then take your pick, they are in the same class. Choose the May if you like two teaspoons of sugar and a little extra cream in your half caf coffee, the 005 if you like your coffee “regular”, as New Yorkers say. But for a $2K difference in price the 005 wins. Even if you lean toward the analog sound of the May you can take the $2,000 saved to tweak the 005 to sound more like the May by adding a nice tube preamp or warmer/smoother sounding cables. If you outright prefer the 005, you have an extra $2,000 in your pocket.
dbb
Thanks for taking the time to do the comparison and then telling us about it.  Audiogon could use a lot more of this kind of post.
Great post and comparison. It's especially nice to see a review on the Level 2 May. My L2 should be arriving sometime in November, and your description is exactly what I'm looking for.
@dbb,This is an amazing comparison. I don't think I have read a professional review that makes such clean comparison. In my books I had give up on the ESS DAC chip - not because of the poor implementation in some cheap DACs, but because they are all over. But from this comparison review, I think that would be a mistake. At a much lower price the 005 seems to be a winner.
Did you try the I2S on this DAC? Just curious.

Thanks to all for the kind words. It was a lot of work, but also a lot of fun. Nothing like retirement for permitting this kind of project. 

I do not have a high quality d to d converter to give I2S a serious comparison to the usb, though I very briefly tried the I2S with a Singxer su1. The usb was superior.
I've been using 005 for some time now, dbb description spot on. I would characterize 005 as exciting listen, micro dynamic capabilities amazing in my setup, attack and decay in equal proportion. Bass response reaches deep and remains controlled, highs in proportion to rest of frequencies, not spot lit. Sound staging and imaging capabilities will be limited by rest of system, 005 capable of life size, fully dimensional images. 005 resolving powers certainly not lacking per usual  with Sabre chip dacs. Dual 9038pro, much silver wiring, great clocking all contribute here.
In spite of my enthusiasm, I can see where 005 may not be everyone's cup of tea. What I call exciting my be incisive to some, 005 not going to be forgiving enough in some systems. Its not trying to replicate analog, vinyl signature, it can be brash and boastful if the music calls for it. This is dac for those who appreciate inherent and distinct digital sound qualities.

@milpai  I have Singxer SU6, never had the inclination to try I2S input, usb input that good. Still remains intention to try at some point.
Great review! I've got a Holo May Kitsune and totally love it; it's replaced the DAVE and M Scaler in my headphone system and sounds great with my Eddie Current Studio B amp! Never heard of LKS Audio, but that's pretty cool! 
Excellent and clearly stated comparison also very well written thanks dbb.
Very well written. All you “professional” reviewers and editors take note: dbb just blew  all of you out of the water. Clear concise prose.  Bravo.
Great, concise review. People here can learn a thing or two from your style (I did). 😄

All the best,
Nonoise
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Thanks for the review.  I caught wind of this a week or two ago over at hifi-head and have been watching for it.  I upgraded from the lks 004 to the Musetec 005 a few weeks ago and am very happy I did.  I was contemplating delaying the purchase to save up for the Holo May; now I’m glad I didn’t.  For anyone wanting the 005, I can tell you that the Chinese Ebay seller “Annie-audio” is trustworthy.  I had a great experience and you can choose from silver or Black.  Three cheers for the 005!  Jonathan.  
Excellent write-up. Especially appreciated is the choice of music (differing from the majority of DAC reviews) as I'm a classical lover.
Thank you very much! Great review!

I was seriously looking at the Holo Spring KTE and the Musetec LKS 005, but with your excellent review I would say at the direct 3k to 3k price point the LKS 005 wins out then, especially if it has some distinct edges over the May. Impressive.

Very helpful and again thanks for your detailed review and discerning ear.
Thank you for sharing, Digital. One of the very best reviews I have ever read.  I wish others would emulate you when talking about a particular unit. 
I did find very useful the playlist you selected for the test and the factors considered for each choice.
Last, I thought your coffee analogy was brilliant.
I look forward to your future postings

One of the interesting things about this review is that it takes those of us who can remember, back to a different time in audio reviewing.

This was when a review was based, not on the reviewer’s preference for particular sounds, but on his determination of how accurate the component was to the sound of unamplified instruments in real space. This was The Absolute Sound in its original, not its current, incarnation. IIRC reviewers then were required to be regular unamplified music concert goers. In fact, Harry Pearson had an adjective for "sweeter and softer . . . even more so than actual live music." He would call such a component "euphonic," and in context it had a special meaning.

The saving grace of all of this, from HP’s point of view and many of his readers is that if a component did well reproducing unamplified instruments in real space, it would do equally well on everything else. He celebrated a large number of pop and rock recordings.
@melm   I always listen to many different genre of music during listening sessions, sometimes get lost in these sessions listening to the more highly processed recordings. Over time I may feel dissatisfaction with sound quality, begin to emotionally disconnect from music. At these times I always go back to the more natural recordings,  reconnect emotionally.After the reconnect, I can then go back to the more highly processed recordings. Duration is my problem, manipulated soundscapes okay when interspersed with more natural fare, are judged appropriately. Multiple manipulated recordings played in sequence make me doubt sound quality of system, the more natural recordings bring me back to reality.

And you and HP correct in that the better your system does with natural material the better it should do with the manipulated recordings. This is where the rubber meets the road in regard to equipment changes and evaluating sound quality. Assuming greater resolving power with equipment changes, natural sounding recordings should sound better, this may not necessarily be so with lesser recordings. What we want is more resolving power along with proper timbre, tonality. This is where 005 met my criteria for being capable of natural, lifelike performance. 005 not only made natural recordings sound better, but the processed as well. I can now emotionally connect with lesser recordings I couldn't formerly connect to, I just can't do it for long duration. I believe this is how things should be, the artificial should not be long tolerated by our senses.
Sns: You make an interesting point. To me there is something more enduring or less tiresome about the sound made by traditional natural materials put in vibration: brass, wood, strings, animal skins, and human vocal cords. A good question is can electrically produced or processed music become classical years from now. I think the answer is yes. Some may be by virtue of the lyrics mostly, maybe some by the sound. Think of the difference between the words classical and popular. Shakespeare's plays started out as popular but became classic. Maybe the same with Bob Dylan.
And so, what would music we call classical today become? Are you saying it will cease to exist, or that popular forms will go under classical label. We already have 'classic' rock, but I assume everyone knows that different from classical. Certainly, classical music may not be heard by many today, what with music appreciation classes in schools increasingly eliminated and classical music radio stations fewer.


@milpai Re: your question about using the I2S inputs on the Musetec. My old DAC had I2S inputs as well, and I did some research thinking that if one used an ethernet to I2S converter you might gain something by bypassing the USB stage altogether. What I found was that there were not many such units, for there are not that many DACs with I2S inputs. A few that I identified were very expensive and it was difficult to find any safe way of knowing how effective they were. There was one at a reasonable price (under $1000) reviewed by Hans Beekhuyzen. He found that it worked about as well as an SOtM sMS-200 on his Mytec Brooklyn DAC. And that DAC does not have a very sophisticated USB to I2S conversion. As I was using an SOtM sMS-200 Ultra NEO there didn’t seem to be much point in pursuing this.

Moreover the Musetec DAC appears to be optimized for its USB input. It uses an Amanero Combo 384 interface USB to I2S board with femto clocks that measure better than the Crystek clocks used on many premium DACs. It also has one of the most sophisticated power supplies made for a digital side which consist of two banks of super capacitors that are functionally continuingly recharged batteries. Of course the 5V from the USB cable is not used which probably increases the quality of the digital signal in most USB cables you might use.
@melm,Thank You for responding to my question. I was curious because a couple of other DAC advertised the I2S advantage over USB.This 005 DAC is interesting because of it's price to performance factor. But the issue seems to be that there is no local dealer. The Bricasti M5 seems to be the competitor for this DAC (in my opinion).
Lack of dealership  is part of Musetec business model, likely part of price/performance factor. Having said that I purchased mine through Apos Audio out of San Francisco, they no longer carry. Shenzhen Audio still sells, they are trustworthy IME.
Seems likely Musetec does self distributorship; that and relative low cost of Chinese production equals low cost/high performance ratio. Looking closely at parts components would lead me to believe this would be $10k dac if produced in the west with dealer distributor business model.
Nice write up, thanks for taking the time to share. Seems like the Spring3 at ~ $3300 is more of an apples to apples comparo though. The custom USB on KTE lines by all accounts appear to be superior than other inputs (in the HOLO products).

The USB and other inputs in the 005 may fair differently. The amenaro boards have been so slow to adopt/support, a bit frustrating (T+A and others). If I understand correctly (please correct me if I’m wrong), the 005 was tested with the Zen and the May with laptop direct? If so that could potentially change each DAC’s presentation, again not apples to apples.

R2R and delta sig are so very different technologies. Implementation is king for sure. Based on some of the descriptions in the review, the characteristics "seem" to follow those technologies in that the 005 has more of an analytical flavor (sabre) and the R2R a bit more analogue. Again system dependent for sure. 

There are no winners or losers (comparing audio components) - that's impossible to affirm.  It's only, can only be personal preference.

I suppose in many ways (short of hearing actual said product), nowadays one must line up as many reviews to get a sense of a products overall performance to see if it lines up in one’s own preferences? One must always remember this is but one persons ears, with their equipment, in their room etc..

This is not Spring dac. He is comparing Holo MAY LEVEL 2, which has exact same usb implementation as KTE version.
@sns
I understand and well aware - I stated that the new Spring3 would be more apples to apples (similar price, single chassis etc.).  I'm also aware may level 2 has the custom (Titanis) USB
@redlenses03 As I read this review and with the OP evidently trying hard to make it fair, I think each DAC was tested with each laptop set up the same. If I’m incorrect, I trust the OP will be heard from.

You describe the OP’s conclusion somewhat differently than he does. You have the 005 with an "more of an analytical flavor" and the Holo "a bit more analogue." The problem is that "analytical" and "analogue" are loaded words in this context and you may be betraying a bias. (We all have biases, including me.) As I read what the OP has written, the 005 sounds more like the live unamplified music he has experienced. The Holo sounds, he writes, "softer and sweeter" than the live music itself. In other words: what we used to call colored or euphonic. When you write "analogue" (even as distinct from analog) perhaps you mean more like vinyl, which itself connotes a particular sound.

As I wrote earlier, there is a difference between personal preferences in sound, and accuracy to unamplified instruments in real space. At its origins The Absolute Sound made those distinctions clear. They have been lost in our own time. Each of us has different experiences with live sound and may be spending a lot of money on this stuff. Of course we are entitled to pick as we choose.
Looking at the internals of the 005, is it just me or do the builds between holo and 005 look similar?  Either way, both have ridiculously good build quality
@melm Yeah it is a challenge to articulate all of the audio terms and as you pointed out everyone sort has there take.  Clear/edginess > analytical side, warm/sweet = analogue'ish, but point taken and I get what you are saying :) 

The OP did a great job explaining and conveying what he heard.  Great time to be in audio for sure.
@redlenses03   I'm afraid you did it (showed your biases) again.
Can we agree on:  Clear/detailed > naturalistic side, warm/sweet = analogue'ish?  That would be more . . . . . . . clear.

I can think of deprecating adjectives for both sides, but I'm trying to be diplomatic.  These are two very fine DACs.  No need to apply negatives to them (most especially without an audition). 
@melm
I haven't (intentionally) applied negatives to anything, not in the least.  I think we're talking a bit past each other.  It's all good.

Analytic, warm, clean, neutral, vivid etc.. are all traits, non of which are negative.  They all have their place and I'm not on any side, didn't know there was one. 

All the DAC technologies really come down to design implementation.

In any case these DAC's appear to be fantastic products, that punch way, way above their price. I'd love to hear 'em.  Pick your poison :)

@melm
@redlenses03

The 005 was connected via USB  to an Asus mini Windows computer while the Holo Audio May was connected via USB to an Asus laptop. I don't think there is any discernable difference in sound between the two computers. In terms of source I think it is close enough to apples to apples.



Thanks for the clarification, sorry if I misunderstood the connection setups. 

Awesome you were able to compare side by side - that's usually difficult to do.  Enjoy in good health!
@milpai   I think it is the Bricasti M1 (at about $10,000) that is the closest competitor in that line to the Musetec.  The Bricasti, though, has an additional streamer feature with an ethernet input.  

As for local dealership, I think of myself as a pioneer buying a Chinese DAC directly many years ago.  Given the advantage in quality/price ratio I have often been surprised at the resistance of others to do the same.  Since we're in a Musetec-Holo thread, let's compare.  You cannot audition either in advance.  Kitsune (Holo) offers a "10 day customer satisfaction policy."  But in addition to shipping, the customer pays a 15% restocking fee.  Do the math.  If you purchase a Musetec from Shenzhen Audio, there is a "30 Days No Reason Return."  You pay shipping.  Even so, If I wanted a Musetec I would apply directly to the factory.

In both cases, for any warranty work you deal with the factory.  Kitsune: "All product warranty coverage after 30-days will be handled directly by the product manufacturer."  That would generally mean that you try, with the manufacturer, to identify the problem, open the DAC, lift out a circuit board and send it in for repair.  The same with Musetec.  

If you want the local audition and the intermediation for warranty work, you pay for it.  Look at the popular "DAC Shootout Starts This Weekend" thread on this board.  It's mostly about high priced, high mark-up DACs. Quality/price ratio?  Not so much.



@melm This kind of analysis should be helpful to potential buyers who in the first instance assume similar price means similar quality. Holo Audio is not really a factory direct discount operation. You pay for the US distributor who is primarily a sales agent and marketer. You can’t buy directly from the factory. Not so with Mustec, which can be bought factory direct for $2700, with a one year warranty period.

You make a good point. In terms of warranty service you get the same deal from each: send it back to the factory, I assume, at your expense. Return policy is actually worse for Holo Audio/Kitsune. Since they recommend 3 weeks of break in, and the buyer only has 10 days to decide. You would have to return it before you even knew how it sounded. I don’t know if Mustec has a factory direct return policy, but you can get the 30 day return through its Chinese retailer shenzhen audio, as you mentioned, but you will pay a few hundred dollars more.


@dbb Where can you grab the Musetec for $2,700?

Really interested in giving it a try.

Thanks for the excellent review!
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@ja_kub_su Sorry, the factory direct price I paid in April was $2,800, not $2700.

The Musetec email address is: [email protected]. It is on their website at http://www.mu-sound.com/
This has been a wonderful, nuanced thread. I would love to listen to the Musetec and do a detailed comparison between it and some higher priced DACs I own or have home demo'ed recently (I own a totaldac; have had weiss, chord, and naim in the house). The trading market for Musetec is almost nonexistent unfortunately --  unless someone in NY wants to lend me one, I may just order a new one for kicks...


I'd love to hear your take on the Musetec compared to higher priced DACs. Where are you in NY?
Donnedonne, funny you should describe thread as wonderful and nuanced, reflects 005 sound quality as much as owners of 005. Have to say I've only had enjoyable interaction with other 005 owners, just not enough of us at this juncture!
@dbb I'm in Manhattan :-)

FYI that the current factory price appears to be $3000. I don't expect I can get an "Audiogon reviewer" accommodation lol...
In a way this thread has become one of the more interesting as it gets to the heart of what different listeners want in a sound product. I believe that stretches well beyond DACs to all manner of audio equipment.

I remember similar discussions in the early vinyl days--with the choice of moving magnet (MM) or moving coil (MC) cartridges. There were those who swore by the comfortable listening benefits of the better tracking MMs, notably the Shure V15 series. On the other hand there were the early affordable MC cartridges that sounded a bit rough, but detailed and colorful. Remember the original high output Sumiko Blue Point or Blue Point Special? But they gave us another way of hearing the music bringing us closer to the real thing in some ways. Well the MMs developed in a way which gave more detail and color bringing them closer to the MCs. The affordable MCs developed in a manner that smoothed out the harshness and, dare I say, brought them closer to the more modern MMs. Differences still, but moving closer together. Sound familiar?
Awesome review. Thanks for taking the time to do that. I am very close to pulling the trigger to buy the 005. I am currently using a Holo Audio Spring 2 KTE. 
Coming from Delta sigma DACs, the Spring took some time getting used too as it first appeared to be dull, soft, and lacking detail. After some other upgrades, I now understand the attraction to NOS R2R DACs.

One point that I am not sure on with the 005 is how sensitive it is to the feed from the source. The Spring in NOS mode is very sensitive to what feeds it. I use Roon/HQPlayer to feed the Spring and can really tailor the sound. Unfortunately HQP is very finicky in my setup so I have recently had to use Roon to upsample DSD. Even though I can do DSD256 in Roon it feels lacking in comparison to DSD64 in HQP. 
Just curious if anyone can comment about upsampling to the 005 or other similar DACs. My guess is that it would be far more important in a NOS DAC such as the Spring.



I only use JRiver with the 005. It can upsample, but it may not be comparable in quality to HQPlayer. I've noticed very little difference as the quality of 44.1 is so good. In fact, I'm not even sure the native DSD files I have sound better than the 44.1 rip of the hybrid layer. With DACs I have owned in the past, I could not say this.
Thanks for the note on your experience with JRiver.  I a, glad to hear that.  It is startling how much of a difference the source makes on the  NOS mode in the Spring.
@sruffle
As to how the Musetec would fare being fed upsampling by HQPlayer, you might look at the experience with the LKS MH-DA004 DAC made by the same company. From the ESS chips through the analog stage the basic design is similar. However the Musitec is implemented at a much higher level both at the analog section power supply and at the section itself. And the digital section is entirely different.

At the LKS Head-Fi thread, https://www.head-fi.org/threads/lks-audio-mh-da003.745032/, there is much talk about success with HQPlayer upsampling. "Upsampling to DSD512 is awesome to say the least!" "External DSPs like HQplayer do a far better PCM -->DSD conversion" were some comments. A search on HQPlayer in that thread will come up with more experience. Depending on the contributor, their DAC may have gone through modification ranging from slight to substantial.

That being said, the Musetec does a much finer job than the LKS on all the digital configurations so any sonic improvement may be more subtle than on the LKS. Perceived improvement may depend upon surrounding components and your own sensitivity. But it looks promising.