Six DAC Comparison

@stuartk

"We are talking about the law of diminishing returns here, no?"

I would not argue with that. IME, the relationship between cost vs. performance is more logarithmic than linear. As you move along the curve, it begins to take more money to achieve smaller gains. However, from my post yesterday, I quoted reviewer Michael Lavorgna, "While this difference wasn’t huge in ultimate terms, I find when I’m in the listening zone even minor differences can be important." I agree with his point that for some, it may be worth the extra money to achieve certain specific, small to moderate sonic improvements.

The trick IMO is to figure out your personal, "good enough". Sometimes that limit where a system is "good enough" is defined solely by one’s wallet. Other times, it occurs when the entire system reaches an equilibrium where all the components and speakers are equitable from a price/performance relationship and the result sounds good enough to be enjoyable without further upgrading. When a system achieves that level of equilibrium, one further upgrade may set into motion the need for another whole round of upgrades until the equilibrium is achieved again. Finally however, some are never satisfied and continue to chase their personal vision of the "absolute sound."

"Just to be clear. I’m not in any way denigrating or doubting what the more costly DACs offer. I’m merely wondering whether choosing a 4K DAC, I’d actually be aware something was "missing". There’s obviously only one way to find out."

Only you can make that decision for you. Of the DACs I have compared, I have no doubt many will be perfectly happy with the LTA Aero DAC and many others are already happy with the Benchmark DAC3. However, out of the group, and in my world, the top three are ahead of the rest. Although I could live with all of them, I prefer the two Mojo Audio DACs and the Merason, which has really continued to impress me. Of those three, I will not keep more than two. The SMc Audio DAC, which I will be keeping, is not far behind the three mentioned but will probably not make it into my main system except as an occasional visitor, simply because I enjoy the others just a little bit more.

MOJO AUDIO MYSTIQUE X SE NCZ

Mojo Audio Mystique X SE Reviews:

Stereophile – by Herb Reichert, April 2023

Stereophile – follow up by John Atkinson, May 2023

The Audio Beatnik – by Ken Redmond, November 2022

Enjoy the Music – by Dr. Matthew Clott, December 2022

Audiophilia – by Karl Sigman, September 2022

Audiokey Reviews – by Oliver Masciarotte, May 2023

The Sound Advocate – (Mystique X) by Howard Milstein, October 2022

Steve Hoffman Forums – by Mfisher 702 (and other posters), March 2024

Steve Hoffman Forums – by Steve Hoffman (and other posters), May 2024

Mojo Audio Mystique X ’24 DAC

 

Mojo Audio Mystique X SE NCZ

The Mojo Audio Mystique X SE NCZ, is their flagship X SE DAC that has been upgraded with nanocrystalline (NC) chokes, and “Z” designated DAC chips. I believe this is the best DAC Mojo Audio offers at this time. The current top DAC is called the Mystique X ’24, which I believe is the same DAC available with either ferrous (FE), amorphous (AM), or nanocrystalline (NC) choke choices. The main difference between the X ’24 and the DAC I have here is that the AD1862NZ chips are no longer available.

If you have read my write-up on the Mojo Audio Mystique EVO Pro DAC earlier in this thread (9-14-24 @ 1:12pm), then you know how much I have enjoyed listening to the five different Mojo Audio DACs I have owned. The Mojo Audio Mystique EVO Pro DAC has been my reference in my main system for a couple of years now, and I even chose to keep that DAC over Mojo Audio’s Mystique X SE DAC, when I originally owned both of them.

Creation of the Mojo Audio Mystique X line was a necessity brought on by the events of 2020/21 that resulted in supply chain disruptions, and shortages of parts and materials. Prior to that, Mojo Audio’s Mystique EVO Pro was their former flagship DAC, and the highest version of their Mystique EVO line of DACs. Mojo Audio originally had plans to further upgrade the EVO line, and possibly offer an even higher-level version of the EVO using BB PCM63 DAC chips. Difficulties procuring key parts, including the specially coated aluminum chassis used on the EVO series, caused Mojo Audio to cease production of the EVO line (although it is fully supported) and travel a different path.

The goal, in the words of Mojo Audio’s owner and designer, Benjamin Zwickel (Benjamin), was to create a “a lower cost alternative with similar performance” to the EVO line. This would be accomplished by using more readily available parts, different design choices, and less labor-intensive manufacturing processes. The new DAC design would be housed in an extruded chassis that requires less aluminum than the EVO chassis, utilize PCB mounted connectors, use a lower number of Belleson regulators, and ideally the product would have been robotically assembled instead of 100% hand built.

Improvements incorporated into the X DAC line included the inclusion of a USB input cut-off switch, the use of better parts in key areas such as ultra-fast, ultra-low noise zero-recovery SiC (Silicon Carbide) Schottky rectification diodes, and new anti-resonant treatments. If you want specific details about the development of the X line of DACs, search the Audiogon forums for posts by Mojo Audio’s owner and designer, Benjamin Zwickel (aka. Fuzzbutt17 on Audiogon).

The end result was that Mojo Audio released a new line of DACs in 2022 designated Mystique X (for extruded chassis). Somewhat surprisingly, the initial feedback by most listeners was that the new Mystique X line sounded better than the former top dog, Mystique EVO Pro. Benjamin shared the following observations about comparisons to the EVO Pro:

“Even though the Mystique X uses the identical circuit and nearly identical parts to our Mystique EVO, due to the new chassis typology, shielding, and anti-resonance, the Mystique X has a notably lower noise floor than any DAC we’ve ever offered. As you lower noise floor you not only reveal low-level details which were formerly masked by noise, you expand dynamic range. The Mystique X has insane micro-dynamics.”

And,

“To my ear they [Mystique EVOs] sound a bit slower, softer, and a bit vague when compared to our Mystique X.”

Benjamin’s post in this thread on 09-15-24 provides more detail.

The Mystique X SE is the upscale version of the Mystique X. The DAC that is the subject of this write-up includes nano-crystalline (NC) chokes and special AD1862N-Z chips, which were reportedly produced back in the day for higher level Dennon CD players, but are unfortunately no longer to Mojo Audio. The Mystique X SE NCZ DAC had an original retail price of $12,499. The current Mystique X ‘24 is available with NC chokes (but not Z-chips) at a retail list price of $9,999.

Ok, so how does it sound? There is something I like about the Mojo Audio DACs that I don’t quite hear from other DACs that I have owned or tried in my system which, including those listed here, include Metrum Acoustics’ Pavane and Adagio, Aqua Acoustic’s La Scala Mk II, and Ayre’s QB-9 DSD. Benjamin would probably say this is related to how Mojo Audio’s R-2R DACs display the true time, tune, tone, and timbre of the original musical performance.

Without going too deep into detail, on song after song of my test tracks the Mystique X SE NCZ did indeed display something special in the way it reproduced dynamics and harmonics that give music energy. Both female and male vocals were rich, full, and resonant. The instruments playing sounded as intended, with no absence of body or detail. The relative amplitude of each instrument was consistent with the performance, which helps lock in the staging, and the ability to instantly go from soft to loud made music exciting to listen to regardless of the playback level. As I said of the LTA Aero, “that… [ability to sound exciting at any volume level] is not an easy trick to pull off but it does enhance the engagement level of listening to recorded music in your home”.

I decided to play some of my test tracks at a relatively high volume, centered around 80dB +/- on my Decibel X app. On "Birds", by Dominique Fils-Aime’, the bass was subterranean, without any blurring of detail, and without affecting the mid or high frequencies. The Mystique X SE NCZ has the ability to enhance the dimensionality of players and singers, sort of like the LTA Aero did when it was here, but without sounding forced in any way, and with a greater level of refinement. This level of energy deviates a bit from the comparatively more relaxed sound I have become used to from the EVO Pro but doesn’t take away from the realistic sound of each instrument playing on "The Girl from Ipanema" and especially the dynamic sounds from Getz’ saxophone, which sounded so very real, and Astrud Gilberto’s innocent, breathy sounding vocals (amazingly, this was her first professional session in a studio – here is an interesting but sort of sad read).

Susan Tedeschi has incredible vocal control and does an amazing job of using tone, pitch, and amplitude to display passion and emotion. Through the X SE NCZ her vocals on "Angel from Montgomery" were on full display, as well as Jason Crosby’s fiddle and the rest of her band that night in Austin, Texas.

I neglected to adjust the volume control as the test tracks were playing and ended up listening to "Smells Like Teen Spirit" at 90+dB! No breakup, no fuzziness, scratchiness, or other nasties whatsoever. The X SE NCZ simply delivered what was on the recording with everything in its place, it was just louder. Same with Gov’t Mule’s Thorazine Shuffle. The Mystique X SE NCZ simply plays music, whatever genre you choose to play at whatever volume you choose to listen at.

The last ground I will cover in this write-up is the most difficult - how does the Mystique X SE NCZ compare to my Mystique EVO Pro? When I first owned the Mystique X SE (non-NCZ) I enjoyed both that DAC and the EVO Pro but ultimately chose to keep the EVO Pro and sell the X SE. After purchasing the Mystique X SE NCZ earlier this year, I posted a mini-review and comparison between that and my EVO Pro on Audiogon (mitch2, June 29). After re-reading that post, I could not find anything significant that I would change. To summarize, IMO:

• The Mystique EVO Pro Z has a sweeter, fuller sound compared to the Mystique X SE NC Z, which I found more incisive, impactful, and a touch more detailed.
• I perceived the Mystique X SE NC Z as being more dimensional (articulate positioning of musicians) while the Mystique EVO Pro Z was more homogeneous (musicians in the mix).
• The Mystique EVO Pro Z seemed to have slightly more fluid and sweeter high frequencies while the Mystique X SE NC Z seemed more precise and energetic (although neither are what I would consider edgy).
• Both have relatively powerful bass with the Mystique EVO Pro Z sounding big/full in the bass frequencies, while the bass from the Mystique X SE NC Z seems a bit more impactful and defined.
• Based on my time with the non-NCZ version of the X SE, I believe there are benefits to the NC chokes and Z chips as I recall a slightly dryer presentation from the non-NCZ version, that I do not perceive with the X SE NCZ or with the EVO Pro.

In summary, the reviewers universally love this DAC, and I suspect most audiophiles would find the Mystique X SE NCZ to be a good blend of drive, dimension, tone, smoothness and richness. I find the Mystique EVO Pro Z to deliver all of that while trading off a bit of drive, incisiveness, and pinpoint dimensioning for a richer tone and a bit sweeter, maybe more forgiving, presentation. These differences are not monumental and my observations above do not seem to be wholely inconsistent with Benjamin’s statement that the Mystique EVOs “sound a bit slower, softer, and a bit vague when compared to our Mystique X.”

I appreciated the comparison by Dr. Matthew Clott who has also reviewed both the Mystique EVO Pro* and the Mystique X SE, for Enjoy the Music, and who said:

“The Mojo Mystique Evo (Pro)* is not the most resolving, not the most dynamic, certainly not the most recognized, not the warmest, and not the most expensive. What it is, is one of the most musical, engaging, flexible, bulletproof DAC’s I’ve heard at any price....There’s virtually nothing to dislike, and a whole lot to fall in love with.”

And,

“The X evolution has improved upon the level of resolution, low-frequency harmonic coherency, reduced noise floor, and turned up the level of emotional involvement another notch.”

* Dr. Clott originally wrote his Enjoy the Music review of the older Mystique EVO DAC believing it was the Mystique EVO B4B but later found out the DAC he reviewed was actually an EVO Pro.

Karl Sigman also reviewed both the Mystique EVO Pro and Mystique X SE (non-NCZ) for Audiophilia, and said:

“With a significantly smaller size and weight, and a significant increase in sound quality that reveals hidden gems even in 16/44.1 files, while retaining the unique and special sound quality of Mojo Audio’s Mystique DACS, the Mojo Audio Mystique X SE is a gem itself; it is addictive. A must-hear DAC.”

So, which of the two do I like best? Based on my extended head-to-head comparison between my Mystique EVO Pro and Mystique X SE NCZ, I cannot deny the X SE NCZ is the more impactful sounding DAC. It displays all the positive traits of the EVO Pro, while also exhibiting a bit more of that realistic “you are there” impression. As I have said previously, they are both clearly cut from the same cloth, as you would expect with two DACs that use very similar design choices and parts, and they both sound great. I could easily live with either but if I had to choose only one DAC for my main system it would be the Mystique X SE NCZ.

@brbrock - at $3,959 the Musetec DA 006 should be a direct competitor for market share with Mojo’s Mystique Y that “starts” at $4K.

In the next day or two, I will post a short “wrap” on how the six DACs ultimately compare with each other, at least in my world, and then I will be done unless I get questions.

The DACs I would have added if I had access were the Denafrips Terminator (latest version) and Holo May KTE.  I haven’t heard either.  The DAC that I would like to hear to satisfy my own curiosity is the Totaldac, probably the version Lavorgna has. If it is as good as some say, I would sell the others and buy one.  In the meantime, there are a couple here that sound good enough for me.

Thoughts on Audio Equipment Reviews

While researching information about each of the DACs I compared, I came to appreciate the reviewers who authored the reviews that I linked with my write-ups.  No different from my comments in this thread, none of them are a “final authority” on audio subjects or the particular objects of their reviews, and readers should be careful not to mistake a review for fact.   Reviews are more like editorials, which are basically opinions, and inherently slanted toward the proclivity, or bias, of the reviewer. 

One commonality to most reviews seems to be a reluctance by the reviewer to overstate weaknesses in the gear under review.  IMO, this is not a failing of the review, but something that requires the reader to be more sensitive to the words written and sometimes “read between the lines” to identify both negative as well as positive aspects of the equipment being reviewed.  It is almost impossible for someone, such as a reviewer, to pick winners and losers for somebody else, any more than I can tell you what type of coffee you like.  In other words, just because a reviewer says something sounds “great” doesn’t necessarily mean you will agree when you hear it in your system.  On the other side of that coin, just because the reviewer finds some aspect of the subject equipment to sound off, not to their liking, or deficient in some way, doesn’t mean everyone will view it the same. 

I believe most reviewers are sensitive to the potential impact their words have on consumer purchases and the resulting tangible financial impact that can have on manufacturers.  Therefore, most are at least careful not to overplay possible negatives that may be reflective of their personal preferences as to how something should sound. 

In short, take any review with a grain of salt, whether professionally published or simply posted in a forum.  There are so many things that can affect a reviewer’s impression of a specific product, such as partnering equipment, the room, the music they listen to, and the bias of the reviewer to a certain type of sound.  Therefore, read reviews for informational purposes but whenever possible listen to the gear (preferably in your own system) and decide for yourself what you like or don’t like.

@curiousjim - No, interesting thought but this will not be a regular thing.

Six DAC Comparison - The Wrap

Ok, time to pick a winner - just kidding, but it is time to stick a fork in this.

Something I learned during this DAC comparison is that good sounding equipment can be achieved in many forms, through many different design choices. Also, not everybody is going to like the same thing. Look at the Tambaqui as an example. Many would rank it in the upper echelons of available DACs. It was essentially perfect but I found the presentation to be a little too pristine, too clean, with a little too much upper frequency detail for my tastes. No right or wrong, it just depends on the sound you like to hear, not unlike the six DACs I compared, which would each have their fans. Hats off to the designers and manufacturers that gave us their vision of good sound through these DACs. Each of the DACs in this comparison was a “flagship” for the manufacturer, five of them are current models, and all of them sounded good.

After living with R-2R DACs from Metrum Acoustics and Mojo Audio over the past 5 years, I still found myself drawn to the Merason DAC1 MkII with its hybrid BB PCM1792A chip. To my ears, it is so very close to the Mojo Audio DACs, in the areas of rich tonality, solid bass, and harmonic weight (i.e., full-bodied and powerful). It is also smoother sounding than any of the other five DACs, followed closely by the SMc DAC. However, even though it sounds really good, I consider it just shy of pushing either of the two Mojo Audio DACs aside as my favorites. My best effort to describe the differences would be to say the Mojo Audio DACs provide more organic texture and granularity compared to the Merason DAC, which sounds smoother and more relaxed. My level of enjoyment from the two Mojo Audio DACs and the Merason DAC is very similar, and I tend to enjoy whichever of the three I am listening to at the time.

The differentiator in my preferences is possibly described by a long-time forum poster under user name georgehifi, who commented on Herb Reichert’s Stereophile review of the Mojo Audio Mystique X SE. Reichert concluded his review by stating:

"The Mystique X SE produced a unique, sophisticated listening experience that presented digital recordings as beautiful, probing, and engaging."

Georgehifi followed up by posting:

“Same happens to me every time I listen to a "good R2R dac", ya just can’t beat em, even if "some" of JA’s measurements are disappointing, as is the cost, there is something that is just fundamentally "right" with R2R Ladder doing PCM conversion, that Delta Sigma misses out on.”

However, it is my understanding the two hybrid BB PCM1792A chips in the Merason DAC1 MkII do not provide a straight Delta-Sigma conversion. Benjamin Zwickel at Mojo Audio explained it like this:

“The BB PCM1792A chips are what is called a "segmented R-2R"…To me segmented DAC chips sound halfway between R-2R and single-bit Delta-Sigma DAC chips…sort of smoothed over by the algorithms.”

So, digital conversion in the Merason is somewhere between R-2R and Delta-Sigma. That seems to correspond with what I am hearing. IOW, I shouldn’t be surprised that I would both enjoy how it sounds and also perceive an additional smoothness compared to the R-2R DACs. I plan to continue acclimating to the sound of the Merason and occasionally reevaluate how it stacks up against the other DACs.

With respect to the remaining three DACs in the comparison, my next favorite for sure is the SMc Audio DAC-2 GT-24, which has great tonal qualities and is pretty good at everything else. I view it as just a touch behind the Mojos and the Merason. The differences are nuances, such as a little additional energy in the high frequencies from the SMc DAC-2, while I perceive the Mojo and Merason DACs to have just a little more flesh and body. While these differences are small, they are noticeable to me in a direct comparison. Regardless, I could be perfectly happy living with the SMc DAC-2 in my main system, and I wouldn’t have noticed those subtle areas for improvement except in direct comparison with the other DACs.

The Linear Tube Audio Aero DAC is no longer here so it is a bit harder to recap. The Aero, as I remember it, was all about energy, with good tone and body. It was a great sounding DAC at its price point, and above, but its sonic presentation simply did not match my tastes to the level of the other DACs, for the reasons discussed in my write-up.

Finally, I appreciate the accomplishment that is the Benchmark DAC3 HGC. Those exceptional measurements, and good sound, at such a low price, opens up the world of high-end audio DACs to buyers operating with a smaller budget. However, the DAC3 is sort of a conundrum in that I cannot point to anything specifically wrong with how it sounds yet it simply doesn’t engage me to the same level as the other DACs in this comparison. I plan to keep it around and use it in my outdoor system where having a DAC with a volume control will simplify things.

Thank you readers for your patience throughout this process and especially to those who shared encouragement and kind words.

@viber6 - The Tambaqui is a very good sounding DAC and based on my time with it, more refined sounding and enjoyable to listen to than the Benchmark, which is still a bargain at it's price.  However, just because they both measure well, doesn't mean they sound the same.  I could live with the Tambaqui in my main system but I prefer the more organic, textural, presentation of the Mojo DACs as well as the  richer, fuller, and more relaxed sounding presentation from the Merason. 

The one I would still like to hear is the HoloAudio May DAC that John Atkinson reviewed, measured, and described as follows.  "In almost every way, the HoloAudio May (Level 3) is the best-measuring D/A processor I have encountered, rivaled only by the Weiss DAC502 and MBL N31."  Regarding the sound, he said, "The HoloAudio May (Level 3) is one of the best-sounding D/A processors I have tried."  If it is really that good, it should be an absolute bargain at it $5,600 price, for the KTE version.  I simply have not heard it and therefore cannot say one way or the other.    

@trentgordon - Thanks for the update.  It sounds like either choice is a win. Interesting that you were able to change the sound of the Aero with different tubes.  I believe Michael Lavorgna at Twittering Machines was planning to post a Part 2 to his Aero review after trying some tube rolling.  It seems that many are interested in DAC comparisons at that $4K price point.

Thank you @curiousjim!

I am listening to a new/upgraded Sonore Signature Rendu SE Deluxe Optical today - long name but great product and great people to work with for customer satisfaction.

BTW all, I am still curious to hear a Holo Audio May KTE, and also a totaldac unity and would add write-ups on those DACs if I had the chance.

If any Holo May KTE or totaldac owners out there are interested hearing a Mojo Audio DAC and would be willing to loan/swap DACs for a month (one of my Mojo DACs for a May or totaldac) with no cost except each of us pays shipping/insurance each time we ship, let me know.

@curiousjim - Sonore have been doing this for awhile now, an optical cable directly feeds the streamer, which is called their Signature Rendu SE Deluxe (optical). SGC is a good place to buy one or, directly from Sonore. I started using optical cable for my 45-foot run from my network room to my system room for a couple of years now (by using converter boxes) but I have been using the Sig Rendu SE optical for just under a year. This new one is fully updated to their latest version (more than just a firmware upgrade).

The sound is clear and smooth, but also full, natural, and with good body - light years from mechanical.

The Sig Rendu SE Deluxe is their flagship one box PS plus streamer board but the real bargain is virtually the same streamer board w/o onboard PS (ultra Rendu) for only $1K, or $1,600 for the optical version. Many are perfectly happy using that smaller version to stream, or as a streamer following a dedicated server. I can’t say how much better the one box SE Deluxe is for between 3x-4x the price, but I wouldn’t go back in my main system, because that streamer plus my SGC sonicTransporter i9 (Gen 4) gives me as good a digital signal as I have heard in my system. SGC and/or Sonore also sell a high quality optical converter and a switch with both Ethernet and one optical connection to help people switch over to using optical signal transmission.

@no_regrets - Yes, I wrote:

"I recall a slightly dryer presentation from the non-NCZ version, that I do not perceive with the X SE NCZ or with the EVO Pro."

That comment is part summation and part paraphrasing from notes I took and emails I traded with Benjamin regarding my impressions from last year of my EVO Pro vs. the X SE that I originally owned, and I believe it is accurate. I did not have the original X SE here at the time of my recent six DAC comparison, but I do still have my listening notes and emails with Benjamin. I was pretty honest with him at that time.

Benjamin calls the EVO Pro "warmer" than the X SE. We may be saying similar things while using different words. Here is an exact quote that I wrote to Benjamin when I decided to sell that original X SE:

"in comparison to the [EVO] Pro, which I found to be smoother and perhaps a little more tonally rich, while only giving up a small bit of bass impact and vocal projection, I simply find the EVO Pro to sound more natural to me."

What I can say now is that the X SE NCZ that I currently own seems to be a closer call against the EVO Pro than both my recollection and notes/emails would indicate from my initial comparison between my EVO Pro and the non-NCZ Mystique X SE DAC. That may be because the Mystique X SE NCZ is a little smoother and richer sounding than the oringinal X SE DAC I owned, it may be that there was an issue of some sort with the original X SE DAC, it could be that my listening preferences have changed a little, or it could be a combination of those things.

I still really like the sound of the Mystique EVO Pro that I have here and I find it to be everything I wrote in my write-up in this thread. I believe Benjamin is right and that the X SE is probably objectively a better DAC from the standpoints of resolution, drive, and low noise, but I am still drawn to the engagement I perceive from my EVO Pro that has AD1862NZ chips. Sorry, but I just don’t have a more definitive answer. I like them both, they are both similar and both sound good, and it is just about a draw wrt which I like better.

Regarding your power question, I am fortunate to live in a neighborhood with all in-ground electrical lines, although there are above-ground transmission lines feeding the neighborhood. It is not an old house so I have a 200 or 225 amp service, and run 3, 20-amp dedicated lines to my music room using 10 awg Romex. The amps get a line, the preamp and volume control get a line, and the streamer, DDC, and DACs get a line that first feeds an Isoclean 60A power conditioner. PCs to the digital stuff are all shielded. The network gear also has its own dedicated 20A line (a fourth line). Since we are not in what I would call a "city environment" and are not close to commercial/industrial entities, I doubt we have the fluctuations you speak of, and I haven’t noticed anything leading to different types of sound at different times of the day. Internet seems adequate also, and is consistently somewhere between 300-400 Mbps.

Michael Lavorgna just came out with his additional review of the Linear Tube Audio Aero DAC  - Part 2 Tube Rolling.

Fairly short and succent (generally a good thing), he tried five different tubes, in addition to the original tubes supplied by the manufacturer, and determined he liked three of the tube pairs better than the others, with his favorite being a pair of NOS Tung-Sol JAN-12SN7GT – Round Black Plate, Oval Mica tubes.  He found that the Tung-Sol tubes,

"offered a nicely balanced sound overall with an added touch of richness in tone and texture and more than a touch of extra air". 

Lavorgna contrasted his favorites with the original GE’s that came with the Aero, about which he said,

"getting back to the original GE’s that came with the Aero it became clear that they offer more apparent detail than the NOS tubes I preferred which emphasized that hardness I mentioned in my first review."

Interestingly, LTA offers two levels of Ray Tubes 6SN7s, Select and Reserve, for purchase separate from the DAC. 

Lavorgna ended with,

"Summing up, the tubes I preferred—

• Tung-Sol 12SN7GT,
• GE 12SX7GT(A),
• Ray Tubes Reserve 6SN7

—all brought out qualities that gave the LTA Aero DAC the kind of richness and rightness that suits my tastes to a T, bringing music to life in Barn and in me to a greater degree."

I find it nice that he took the additional time to share how changing tubes can change the sound of the LTA Aero DAC.  It gives the current and future owners of that DAC something to think about.

 

 

@rfagon - I agree with your assessment of Michael Lavorgna’s reviews of those three highly regarded DACs. I was also interested in reading his perspectives as a single reviewer listening to all three DACs in a single system. His preferences lean towards the totaldac house sound, which he describes as musical, dimensional, natural, and “startlingly present,” instead of solely looking for the best measuring, highest resolution DAC.

Lavorgna uses the word “’crystalline’…to describe the sound of the KTE May DAC” and discusses how it is best paired with amplifiers that present a “softer and more dimensional sound”, and not with highly revealing/resolving amplifiers. As with the May, he advises against pairing the Tambaqui with highly resolving amplifiers such as Ayre’s EX-8 saying, “the Ayre / Mola Mola combination offered a bit too much of a good thing in terms of resolution and clarity where music could adopt a hardness that I found distracting.”

Livorgna says, “The Mola Mola Tambaqui and the Holo KTE May DAC are more closely related, nearly sounding like brothers.” In addition to being resolving and displaying crystalline clarity, the Tambaqui and Holo May brothers both exhibit excellent measurements, while the totaldac house sound that he likes so much comes from a DAC that apparently doesn’t measure well. The measurements of the totaldac d1-six reviewed by ASR were so bad that Amir Majidimehr said, “I don’t think we have ever seen anything as broken as this.”

This seems to bring us full circle to the adage that what measures well doesn’t necessarily sound good to everyone, and the converse about what measures poorly. IOW, regardless of how something measures, you need to listen for yourself. The Tambaqui certainly has its fans but, in a direct comparison, I preferred the sound of my Mojo Audio DACs over the Tambaqui. I respect the accuracy, power, resolution, and musicality of the Tambaqui but, to me, the Mojo DACs sound richer and more natural, which are traits I appreciate and enjoy. However, like the totaldac, the Mystique X SE also doesn’t measure that well, at least according to John Atkinson at Stereophile.

I have been enjoying the Merason DAC1 MkII here, which uses a hybrid chip, but I have no idea about how it measures since I haven’t seen a review of the Merason with measurements. However, as with Michael Lavorgna and his totaldacs, I keep coming back to the sound of my two Mojo Audio DACs as being more natural, even if they are perhaps not quite as refined sounding as the Merason or as well-measuring as the Tambaqui. Here is an interesting write-up about the different DAC levels in the Mojo Audio Mystique X line, as you progress from the Mystique X, to the X SE, and then to the X SE NCZ version that I currently have here.

@stuartk

"do the Mojo DACs require tube amplification to sound "natural?"

Not in my system, which is posted here on Audiogon. SMc Audio solid state preamp and two SMc Audio solid state monoblocks.

Another interesting article/post on that site is which provides one writer’s perspective on different categories of gear. If you look at the DAC list, you will find the Mystique EVO Pro 21 in the Holy Shit!! tier, but the X SE was apparently not listened to. It does provide a perspective on the Mojo Audio house sound, although IMO the X models move away from the "coloration" mentioned by the writer. However, OTOH, I believe what he calls "coloration" is a sonic attribute I find compelling on my EVO Pro Z, to the point where I seem to be unable to sell it an settle in with only the X SE NCZ.

@brbrock - I both stream and play local music files.  My digital front end is outlined on my virtual system page and essentially consists of playing either files recorded in FLAC and stored on a SSD inside of my sonicTransporter i9 (Gen 4) server, or music streamed from Tidal or Qobuz over Roon, with the i9 serving as Roon Core and a Sonore Signature Rendu SE Deluxe Optical as a streamer and Roon Ready player. 

Streamed music and and files played from my local library sound so close to each other that I have not spent time trying to discern whether I can actually and consistently hear a difference.   

Mojo Audio DACs are PCM based and as mentioned on their website, 

"Our Mystique X digital-to-analog converter converts PCM format files up to 24-bit 192KHz via Femto clocked USB, coaxial S/PDIF, or balanced AES."

I believe Benjamin has spent quite a bit of effort on the quality of the USB input in his DACs and especially since his newer, Mystique Y DAC offers only a USB input.  In my case of owning five different Mystique DACs, I heard pretty much the same thing as what you stated, that there just isn't much difference between the inputs except that the "USB might be slightly darker".   However, I have never had to utilize different drivers since my servers and streamers have all been Linux based.

@debjit_g -Below is a quote from this review article.

“Along with all the premium parts mentioned above, the X SE employs JL Sounds’s USB–to–I2S input module. In macOS’s Audio MIDI Setup, it was nice to see the unit listed as “JLsounds Hi-Rez Audio 2.0”.”

 

@zmann007 - you are correct about the XMOS receiver chip, although JLsounds is apparently still involved wrt drivers for Windows.  I used to see JLsounds come up when I opened mysonicorbiter but since I now run the USB into a DDC and then use S/PDIF or AES/EBU into my DACs, I don't see that anymore.  If important to @debjit_g then I suggest he emails Benjamin with any questions.

This below is from the X owner's manual and seems consistent with other information on the website.

USB Input

Our USB input uses a high-performance XMOS receiver chip, is galvanically isolated, asynchronous, and has ultralow-noise femto clocking. To completely isolate the digital and analog power supplies on the Mystique X our USB input module has it’s own secondary on the power transformer, it’s own Silicon Carbide zero-recovery Schottky diode rectification, and uses two Belleson SPX ultralow-noise ultrahigh-dynamic discrete regulators, one for input and one for output.

Always power up the Mystique X before booting up your music server or streamer.  Unlike many DACs, the Mystique X uses no dirty USB buss power. For this reason the Mystique X must be powered on before booting any music server or streamer so that the XMOS USB receiver chip is powered on and can be recognized. Because of the 100% isolation and uncompromising performance of the power supplies and the ultralow-noise femto clocking used in our Mystique X, the USB input module performs better than most USB reclockers and regenerators. According to our customers, most of these “magic” USB boxes will degrade rather than improve performance.

Drivers for the USB input module are included in Apple OS X and Linux. If your server or streamer is Windows based the driver must be downloaded:

http://jlsounds.com/drivers.html

Our USB input module will show up in your player software as “Mystique.” In player software that works with video as well as audio there will be more than one option with the name “Mystique.” Select the option for “Front Speakers.” USB Lift We include a USB Lift on the rear of Mystique X which removes 100% of the parasitic power supply drain from the USB input module and removes all internal clocking noise from inside of the chassis. When facing the rear of the chassis, slide the switch to the right to lift USB. One reason many companies recommend single-ended RCA coaxial AES or balanced XLRAES digital inputs is that they isolate DACs from computer and clocking noise.

 

Benjamin's take on clocking can be found in here - scroll down to Myth #1-Clocking.

Regarding I2S, it was primarily designed for internal use - short runs inside of equipment, which may be a reason there is still no universal standard.  When I owned Metrum equipment, I heard no improvement when using the I2S input to my Pavane or Adagio DACs.  In fact, with my system at the time, I liked the sound of the USB input a little better, but that required taking the Ambre streamer out of the mix so maybe it was apples and oranges.  With the Singxer SU-6 DDC, I do have the option of using I2S and adjusting as needed to match specific manufacturer's versions of I2S.  Unfortunately, I have not had an I2S capable DAC here since I acquired the Singxer.  I wish I had it at the same time I had the Tambaqui here because I heard from a dealer that the Tambaqui sounds best through the I2S input, at least in that dealer's opinion.

@bluethinker - Years ago, I owned a LampizatOr DAC 4 and thought it sounded pretty good except the deal-breaker, to me, was that the soundstage seemed overblown or larger than reality, sort of like an image imprint on Silly Putty that had been stretched out.  The larger than life soundstage seemed to be accompanied by a reduction in the visceral impact that I was used to with other DACs and with the CD player I had at the time. 

However, that was a long time ago and I would enjoy trying a Golden Atlantic, Big Seven, or even a Baltic, to hear how they have improved.  I probably never went back to LampizatOr mostly to avoid having tubes again, especially since I have been happy with the sound I am getting from an all solid-state system that I can leave powered up all the time to accommodate my sometimes sporadic listening habits.

 

 

After finishing my initial comparison of six DACs without coming to a final conclusion about which of the DACs I enjoyed most, I decided to devote the past month or so to listening more intently and forming a more definitive conclusion.

I struggled with the words to convey my final thoughts because any of my four favorites provided a very enjoyable sonic result in my system. It seems that maybe, after everything else in one’s system is dialed in, the specific DAC is important but not solely critical to achieving a successful result.

Another outcome of my past month of listening was a better understanding how critical it is to dial-in the every aspect of the subject component and the rest of one’s system in a manner that allows the component to perform at its best. Playing with inputs, cables, subwoofer settings, and more helped me determine that I had initially underestimated the performance levels of the Merason and the SMc DAC-2. Also, by more intently listening, I was able to better discern the differences between the two Mojo Audio DACs.

My final thoughts on the four top DACs are discussed below.

IMO, the Mojo Audio Mystique X SE NCZ is the most capable of the DACs in the comparison and my overall favorite of the six DACs. If I were to choose just one DAC for my main system, it would be the X SE NCZ. The X SE line shares the natural organic sound signature of Mojo Audio’s previous DACs, including the EVO Pro that I still have here, and also displays a level of resolution that extends beyond Mojo Audio’s previous DACs. This is most noticeable in the bass, which is deep, powerful, and defined, with subterranean impact that exceeds what I hear from most other DACs. Continuing through the midrange, the additional resolution is noticeable in the dimensionality and staging of musicians and singers, that are well-positioned in space and more dimensional than with the EVO Pro. The treble is sweet and extended.

The Mojo Audio Mystique EVO Pro has been a very enjoyable reference in my system for a couple of years. It is as discussed in my earlier write-up and is every bit as natural and organic sounding as the X SE line. I have no doubt that many would find it an improvement in musicality, compared to other DACs. Compared to the X SE NCZ, the EVO Pro includes still prodigious (yet fuller vs. more defined) bass, and a bit darker and warmer sonic signature. Sound staging seems more homogenous, sort of like you might hear from a live concert, compared to the X SE line, which seems to stage more precisely wrt the placement of musicians and singers. Some may find the presentation of the EVO Pro to be kinder to lesser quality recordings. It also retains the sweet, clear, and never fatiguing high frequencies of the X SE line.

The Merason DAC1 MkII, in comparison to the two Mojo Audio DACs, is more reserved yet a bit more refined in its presentation. Bass is solid and well proportioned but not quite as impactful. This is easily compensated by adjusting subwoofers. The mids are not quite as dimensional as with the Mojo Audio DACs, and the high frequencies are all present but displayed in more of a supporting role. Everything comes out wonderfully crystal clear in a presentation that is truly reminiscent of vinyl without the pops and hiss. I enjoyed all of my listening to whatever types of music I was playing, and I never wished for something more when the Merason was in my system. It is a wonderful DAC to listen to, and IMO offers a bit more refinement but a bit less excitement, when compared to the Mojo Audio DACs.

In revisiting the SMc Audio DAC-2 GTE-24, I found that even though the DAC-2 will usually process 96 kHz signals, sending it that higher sampling rate signal may be responsible the occasionally raggedy high frequencies I heard during my initial listening. By strictly limiting the sampling rate to 48 kHz, as recommended by SMc Audio, I achieved smooth, clear, high frequencies, good resolution, and nothing less than outstanding sound from the DAC-2 GTE-24. It displays a similar rich tonality as the Mojo Audio DACs, with some of the refinement of the Merason, but a level of excitement that is closer to the Mojo Audio DACs. Bass is solid but, like the Merason, is more proportional than with the Mojo Audio DACs, and can be fully compensated to the desired level of impact by adjusting my dual subs.

FYI, Aries Cerat, LampizatOr, and some other pretty good DACs use a JL Sounds USB interface, so the Mojo Audio DACs are in good company.

In the process of trying different DACs, I found the Singxer SU-6 DDC helpful in allowing me to use multiple types of inputs into the different DACs I tried. Now that I have zeroed in on one DAC for my main system, I will compare the USB out of my Signature Rendu SE Deluxe Optical streamer directly into the USB input of the Mystique X SE NCZ with using the AES/EBU and S/PDIF inputs into the X SE NCZ coming out of the Singxer DDC. Should be interesting.

NCZ refers to the Lundahl nano-crystalline chokes (NC) and AD-1862N-Z DAC chips, which were a special version of the AD-1862 chip used in higher end Denon CD players.  I don’t believe the Z chips are available any longer.  The NC chokes sound nice but IMO so did the amorphous (AM) chokes.  The X-24 AM should be a very nice sounding DAC.

@sns 

"Gaia superior to Singxer in usb isolation on input and implementation of OXCO clock on I2S. Singxer SU6 as good as it is, simply doesn't play in same universe, build quality, design, parts quality in Gaia all far superior.  Meaningful improvement in sound quality reflects this superiority," 

I never owned the Gaia, but I did own the Hermes and had problems with it requiring me to send it back to Denafrips, although that may have been a fluke.  I do see the potential advantage of the Gaia DDC when using Denafrips' Terminator DAC since it offers the ability for clock syncing.

I am not here to argue about sound quality between DDCs, and I am not promoting the Singxer SU-6 so I don't really have a dog in the fight, but I can say that inserting the Singxer did nothing to degrade the sound of my system and that it has worked reliably the entire time I have used it.  Here are links to review measurements of both the Singxer SU-6 and the Denafrips Gaia by the same reviewer.  The SU-6 was reviewed a couple of months prior to the Gaia and below are some conclusions by the reviewer,

"Overall, the Gaia is an excellently performing DDC.
It falls ever so slightly behind some other choices like the DI20HE and SU6 in performance, but the added features, and matching aesthetics with Denafrips dacs may be more important to many."

and,

"Those wanting the absolute best performance should still look to the Singxer SU6, but for the added flexibility of non-USB inputs, 768khz support, dual AES output, and a matching aesthetic for Denafrips DACs, the Gaia is a great choice."

 

@wig - Thank you for the feedback.  It has been satisfying to hear that several folks have used the information from this thread to successfully help with their DAC purchasing decisions.  I really enjoyed my time with the Merason DAC1 MkII and I am not surprised to hear that it is an end-game DAC for some.

I just found out that I may be getting the opportunity to try out a couple of additional DACs, which I will report on.  I can’t say much yet except that one will be at the $10K +/- price point and the other at the sub-$4k price point.

 

Some updates:

• Got around to listing the EVO Pro and Merason DACs since I have too much stuff here.
• Since I am no longer (currently) comparing multiple DACs, I bypassed the Singxer SU-6 DDC and instead directly connected the USB output of my Signature Rendu SE Deluxe Optical to the Mystique X SE NCZ using a Network Acoustics muon USB cable. My initial impression is that this is an improvement over using the DAC’s S/PDIF or AES/EBU inputs through the Singxer DDC. I may be imagining things, but there seems to be an improved purity that sounds right. Listening now and Jerry Garcia’s guitar is so smooth and nuanced on Dark Star.
• I am apparently in the queue to receive a Mystique Y AM DAC that I will listen to and comment on in this thread. Price-wise, that will be in the ballpark of the LTA Aero and sort of the Benchmark DAC3 HGC. There are rumors of another DAC heading this way too so may need to relabel this thread as the Six+ DAC Comparison
• I wouldn’t mind adding a Holo May KTE and/or Denafrips Terminator 15TH to the list, but I don't plan to buy these just to add them. The one that I would most like to add is a Totaldac.

@dantaudio  - Thanks for the kind words, and welcome back to audio. 

If you are looking for information, there is a lot of knowledge here on this site and you can get meaningful responses from the members on just about any topic.  The forum archives are also extensive and cover just about any audio topic.  Since you have just "returned to audio after a significant break", you might enjoy spending some time looking at the virtual systems since many members have constructed unique listening spaces and very effective audio reproduction systems at a wide range of price points.

@wig - I agree, the Merason DAC1 MkII was a hard one to give up. I would have liked to keep it but just had too many DACs here. The Mojo EVO Pro was also hard to give up and the buyer received a very nice DAC with the Z-chips. Benjamin checked it out and adjusted it as-needed to as-new tolerances and then shipped it directly to the buyer.

I remain happy with the Mojo X SE NCZ in my main system and the SMc DAC-2 GT-24 in a back-up role when I want to hear a Delta Sigma type DAC. Since I am done comparing different DACs, I have removed the Singxer SU-6 from the signal chain and now directly feed the X SE by USB directly through the USB output of my Sig Rendu SE Deluxe. I recently compared the S/PDIF outputs of the DDC and the Sonore ultraDigital converter. The sonic performance from using all of these input methods into the X SE is close, but if I had to rate them I would probably put the direct streamer to DAC USB connection at the top, followed by S/PDIF out of the Sonore ultraDigital converter, and then S/PDIF from the DDC. However, I would not bet on being able to reliably discern a difference if I were listening blind. I also have a clocked USB filter coming here in the next week or so that I will try.

Next up, Benjamin is supposed to send me a Mystique Y to hear but otherwise I am done with DACs for now unless I find something interesting. It seems the next significant upgrade/change from Mojo Audio will probably be in 2026, with a Mystique Z DAC based on the BB PCM58 chips.

Happy New Year all!

@cdc - I liked the Metrum DACs, and I liked the sound of the Pavane better than the Adagio (I compared them side by side for a while).  They use DAC chips that Cees designed and had manufactured.  His earlier DACs used industrial chips.  The Metrum DACs definitely sound like R2R DACs but they don't share quite the same organic texture as the Mojo Audio DACs, IMO.  The Metrum DACs are quite clean sounding for R2R and moving up their line adds body and drive, IME.  I still have their Jade serving as DAC and VC in my outdoor system.  You should try and hear one.

@brbrock - As far as I know I am still supposed to be getting a Mystique Y.  I thought it would be here by now so I should check in with Benjamin to find out what's up.  

@wig - Thank you!

@brbrock - Mojo Audio Mystique Y AM ($4,999) is in the house and playing music.  I don't know if I will go into the depth in writing about it that I did with the others but, it sounds pretty darn good right out of the gate.  I basically transitioned directly from my (twice as expensive +) Mystique X SE NCZ DAC to the Mystique Y using the exact same system set-up, and my initial impression is that I didn't really give up much in the transition.

I have been playing with quite a few different IC and speaker cables here lately and having this DAC will be an interesting test of how I can optimize the sound of the Mystique Y AM DAC by changing a cable or two.

The Mystique Y sounds good in my system. 

I am working on a write-up to post here but been a bit busy lately with regular life stuff.  I will try to finish and post something this weekend.  As a preview, no real surprises.  Benjamin has been a straight shooter about both how good it sounds and the comparative differences between the Y and the X SE.

A few words about the Benchmark DAC3 HGC. The Benchmark is like an elusive concept for me. How can a DAC that provides "state-of-the-art measured performance" not sound perfect and, why doesn’t it sound like every other DAC that provides "state-of-the-art measured performance"?

"As with its predecessor, the DAC2 HGC, which Erick Lichte reviewed for Stereophile in February 2014, Benchmark’s DAC3 HGC offers state-of-the-art measured performance. All I can say is "Wow!""—John Atkinson

I am currently playing Benjamin’s Mystique Y AM in my system and I have been comparing it to my Mystique X SE NCZ. For personal calibration purposes I pulled the Benchmark out the other day, let it warm up, and then listened. I was amazed at how comparatively flat and sort-of lifeless it sounded. Sure, it played music, the bass was low, the highs were all there, it didn’t distort the sound, and it wasn’t noisy. However, sort of like fabric on a chair after too much time in a sunny spot, it simply didn’t "pop". Compared to Mojo Audio’s DACs, the Benchmark wasn’t as much fun because it didn’t express the same sense of body, fullness, depth, and tonal color. Does this mean the Mojo Audio DACs are distorting the truth to the benefit of listening enjoyment? Benjamin would probably say not, but, maybe. Hey, so what, they sound better!

The other thought I had was about the Tambaqui, which is another DAC that supposedly provides "state-of-the-art measured performance".

"The Mola Mola Tambaqui offers state-of-the-digital-art measured performance. I am not surprised HR liked its sound."—John Atkinson

Why then, is my recollection of the Tambaqui’s sound so different than what I hear from the Benchmark, when they both provide "state-of-the-art measured performance"? I remember a greater level of purity, refinement, and musical involvement from the Tambaqui than I hear from the Benchmark. At the time I owned it, I felt the Tambaqui was arguably "perfect sounding." I wouldn’t say that about the Benchmark, which doesn’t really do anything wrong, but just isn’t that exciting or fulfilling for me. Ultimately, I sold the Tambaqui when I decided that its version of "perfect sounding" wasn’t really doing it for me - you know, the old Jack Nicholson thing about handling the truth. I like the extra meat on the bones, tonal color, and physicality of the Mojo Audio DACs. I typically tell folks "buy what you like", and so I did.

Mojo Audio Mystique Y AM DAC

(warning – long)

Perspective: Just about everything in this audio hobby, like most things in life, is related to perspective, developed through one’s experiences and other factors.  Since none of us are starting from exactly the same place with respect to our individual perspective, what we hear from a component or system, and how that makes us feel, cannot be universally described or consistently interpreted.  Thus lies the problem with reliably conveying and understanding the intent of an equipment review.

When listening to a Mojo Audio digital audio converter (DAC), first-time listeners may focus on the organically natural sound and rich tonal qualities that transcend what they have previously heard from digital equipment. Several first-time reviewers of Mojo Audio DACs have expressed these impressions in their written reviews.

Those of us who have owned Mojo Audio DACs and heard various models, may be more aware of the differences as the line has moved forward. My first listen to the Mojo Audio Mystique v3 created a more life-like musical experience in my home than I had previously experienced through other converters.  As the basic design progressed through the Mystique EVO Pro, each step improved on the very successful combination of rich tonality, sweet treble, dimensionality, and full powerful bass.  The EVO Pro may have sounded a bit rounded and colored (in a good way), and the bass a bit full-sounding vs. defined, but the overall result was very analog-like and certainly pleasing to hear, at least to me.  The X SE continued the evolution of the brand down a path toward higher resolution, and the implementation of the special Z-version of the AD 1862 chips, as well as nano-crystalline (NC) core chokes, further refined the sound in the X SE NCZ model I currently own.

Trade-offs: Another audiophile conundrum is the desire, yet inability, to “have it all.”  As it is, most of our audio gear balances resolution vs. warmth, leading edge incisiveness vs. melodic harmonics, full-bodied vs. tightly damped bass, a tonally bright and airy vs. warm and dense sound signature, a dynamic vs. relaxed presentation, and the list goes on.  No one audio component is going to float everyone’s boat equally. Therefore, I find it more helpful to look for audio gear that provides a sound I enjoy with the music I listen to, rather than search for perfect sounding gear. In other words, I don’t need the exact truth if I can have a version that sounds good to me.

Seasonings: Of course, any individual piece of kit must be inserted into a system, where it plays with all the other pieces in a specific room, as part of a whole. The peripherals involved in an individual system, including tweaks, room treatments, supports, cables, and more, all make a difference in how things sound, to varying degrees.  While these “seasonings” may not fundamentally change the sound of a component, speakers, or an entire system, they may indeed affect the overall satisfaction one has with what they hear their system.

Most of us have our systems set up for the gear that we own, meaning the tweaks, the cables, and other factors are already optimized to provide the sound we want from the gear we have. Therefore, replacing a single existing component can be an uphill battle for the new component, sort of like being the new kid at school and having to prove yourself without having the home field advantage.  I am fortunate to have on-hand a variety of cables and cable choices, like a cupboard of seasonings, each offering a unique perspective, or shading, on how things sound. My system also allows the use of fully single-ended (RCA) cabling, fully balanced (XLR) cabling, and any combination between.  During the process of listening to the Mystique Y AM, I took the opportunity to try a variety of types and makes of cables.

Introduction: I have spent about a month with Benjamin Zwickel’s Mojo Audio Mystique Y DAC with amorphous core chokes (Y AM).  You can research the specific technical and physical aspects of the Mystique Y DAC on the Mojo Audio website, and by reading Ken Redmond’s review of the Mystique Y NC in Tracking Angle, or Howard Milstein’s review of the Mystique Y (both NC and FE versions) in The Sound Advocate.  Both Redmond and Milstein have also reviewed versions of Mojo Audio’s Mystique X DAC.  Having heard both, as I have, provides them an enhanced perspective on the comparisons between the Mystique Y and the more expensive Mystique X.

My experience with Mojo Audio has been that Benjamin continually pushes his personal envelope to create better performing, better sounding, and correspondingly higher priced DACs.  The X DAC was sort of a sideways step from the EVO Pro, as the X was originally created to solve a supply chain problem by replacing the large, harder to get, coated/damped aluminum chassis used with the EVO Pro for a more available and economical extruded (X) aluminum chassis that is used with all the Mystique X and Y DAC versions.  However, that seemingly sideways step actually ended up moving the ball forward based on the lower noise floor and other sonic improvements resulting from shorter signal paths, better anti-resonance topologies, improved parts, and other factors.   You can read earlier in this thread about my comparisons between the Mystique X SE NCZ DAC that I currently own and the (full-size chassis) EVO PRO that I previously owned (that also used Analog Devices AD1862-Z chips). I ultimately kept the X SE NCZ and sold the EVO PRO, although sometimes I wish I still had both.

The Mystique Y is the newest DAC in the Mojo Audio stable and is unique from a few perspectives. First, the Mystique Y DAC is sort of a step backwards in that it is less expensive (by about half) compared to the current line-up of Mojo Audio DACs. 

The second unique aspect of the Mystique Y is that it has only one (USB) input. As a result, according to Benjamin, Mojo Audio was “able to greatly simplify the digital circuitry because there was no need for an input selector, demultiplexer, or S/PDIF receiver. The AD1865 R-2R DAC chip is directly fed by the USB input module."

Third, the Mystique Y uses a different digital to analog processing chip.  Beginning with the Mystique v3, the Mojo Audio DACs have used the Analog Devices AD1862 DAC chip.  The Mystique Y breaks rank and uses an AD1865 chip, as discussed in a post by Benjamin earlier in this thread and in more depth on the Mojo Audio website. Other than the type of Analog Devices DAC chip and the single vs. multiple inputs, the Y and X DACs are reportedly quite close in both their circuit designs and component parts.

You can read Benjamin’s post in this thread from Feb 16, that explains the Mystique Y is priced at three levels, starting at $3999 for the entry model with ferrous core chokes (Y FE), moving to $5,499 for the model I have been listening to here that has amorphous core chokes (Y AM), and topping out at $6,999 for the (Y NC) model using the same nano crystal core chokes that are in my Mystique X SE NCZ, which retailed for $12,499. 

DAC Chips: The Mystique Y uses an Analog Devices AD1865 DAC chip while the Mystique X uses two AD1862 DAC chips. While there are many factors affecting the sound of a DAC, because the Y and X DACs are quite similar other than the DAC chip used, I suspect the different chips used in these DACs are a significant factor influencing the sonic differences I hear between them.

SoundBsessive have posted a DAC Chips List with comments on many of the commonly used NOS chips.  In their opinion, the 20-bit AD1862 chips used in the Mystique X are “one of the world’s best audio” while the 18-bit AD1865 chip used in the Mystique Y is a “very good multibitnik, 2 DACs in one case (stereo)”.  They seem to hold the AD1862 in higher esteem than the AD1865 but rank them both highly. The reason for two AD1862 chips in the Mystique X is because the AD1862 is not a stereo chip like the AD1865, of which only one is needed in the Mystique Y.

Examples of other manufacturers using the AD1865 chip in their current DAC offerings include, Aries Cerat at one end of the price spectrum, that uses two independent banks of eight R2R matrixes (16 total) Analog Devices AD1865N-K chips in current mode in their $19,000 Helene DAC, and Linear Tube Audio at the other end, where their $3,950 LTA Aero DAC uses a single AD1865 chip, like the Mystique Y.

Ken Redmond described his perception of the sonic differences between the two Analog Devices chips in his Tracking Angle review of the Mystique Y NC where he said, “The sonic differences between the two chips are subtle but noticeable. The 18-bit [AD1865] chip [in the Mystique Y] sounds energetic and exciting, while the 20-bit [AD1862] chip [x2 in the Mystique X] sounds more harmonically dense and liquid.  Both units [the Mystique Y and X] have excellent flow and timing that sets them apart from many other DACs. A choice between the two may come down to the important consideration of system synergy.”  I would add that the type of music you enjoy may also play a part in which of these DACs you will appreciate more.

In his The Sound Advocate review of the Mystique Y, Howard Milstein also discussed the differences he heard between the two chips by saying, “Because of the AD1865 DAC chip in the Mystique Y, it can sound a “tad” livelier, and a tiny bit more transparent, with a touch more dynamism in its overall character. On the other hand, because of the AD1862 DAC chip in the Mystique X, the X has slightly more liquidity, texture, and harmonic content. This can be summarized as a sound that is a bit denser, and slightly more texture-filled with playback content that exhibits a bit more concert hall realism.”

Milstein’s description borrows from Benjamin Zwickel’s own opinion of the sound on hand from the two chips, as stated on the Mojo Audio website and summarized as; lively, dynamic, and transparent (AD1865) vs. liquid, textured, and harmonic (AD1862).

Listening: 

I have added some tunes by Susan Tedeschi to my test playlist that I used to compare the DACs previously discussed in this thread. Her inaugural “Just Won’t Burn”, follow-up “Wait for Me” and “Live from Austin, TX” albums all display her emotion-packed vocals ranging from sweet and pure, to hard and gravelly, depending on the tune, as well as great sounding guitar playing, percussion, piano, Hammond B3 organ, and the occasional harmonica.  Her music serves as a good source for comparing components in my system because of the variety of tempo, tone, and drive, and because I enjoy listening to it. 

The Mystique Y AM consistently shone a light on slower smoother songs like “Blues on a Holiday,” where the Y DAC highlighted the smoothness and rich tonal qualities of Tedeschi’s voice.   The organ, piano, and guitar on the live version of “Wait for Me” were rich and vibrant, and the piano solo left me wanting to hear more.  I noticed no compromises when the pace and volume picked up.

Back to my traditional test tracks, the lead-in bass on “Birds” by Dominique Fils-Aime’ displayed the level of impact I hear from most of the more expensive DACs I have had through here, and her breathy voice sounded great, as did the back-up singers.  From Astrud’s wonderful voice on “The Girl from Ipanema,” to the signature beat on Steely Dan’s “Babylon Sisters”, the ruggedly pure early James Taylor vocals, and horn section, on “Steamroller Blues”, and Sara Bareilles’ silky smooth, emotionally charged, vocals as they climbed to her crescendo on “Gravity”, all of those selections were enjoyable to listen to through the Mystique Y AM in my system.

To close out my listening, I rocked out for a while to Soundgarden, Neil Young/Crazy Horse, Chili Peppers, Audioslave, and Nirvana.  IMO, the Mystique Y handled the harder rock music just fine.  I heard no congestion, straining, or thinning out under the load of the hard-hitting rock tunes and especially engaging was hearing and feeling the beat underpinned with solid Mojo Audio bass. I would not hesitate to recommend the Mystique Y AM as a good choice for those who listen primarily to rock.

Clearly, the Mystique Y AM was an enjoyable visitor in my system.  Was it the perfect guest, I would say pretty close in that the timbre, tone, dynamics, and solid bass drive that make listening to music fun were all there on the variety of music I threw at it. These are the signature attributes of all the Mojo Audio Mystique DACs I have heard, starting with the Mystique v3.  The solid bass provides a platform for the richly textured midrange and smooth treble.  The Mystique Y wears the same team colors.  During its stay, the Mystique Y AM basically did nothing wrong, no discernable sibilance, excess noise, tinny, muffled, or boomy sound, so, basically no party fouls.

Pretty much all good stuff from the Mystique Y AM, especially at the price point.  So, is the Mystique Y AM the perfect DAC for my system and tastes?  Certainly a top contender at the price point.  However, I didn’t hear quite the depth of soundstage or tonal saturation that I hear from my Mystique X SE NCZ, and that I have heard from a couple of the other more expensive DACs that have been through here.  Those improved qualities related to soundstage depth and tone I hear when listening to the Mystique X SE NCZ, increase the sense of musical realism and result in an even greater level of listening enjoyment, beyond what I hear from the Y AM, and other DACs I have had here that were in the $4-7K price range. 

Comparison to the X SE NCZ: It seems a rather high bar for a company to encourage comparisons between their flagship component and the newcomer at around half the price.  However, based on my listening, I agree with the two reviewers, and with Benjamin himself, that the sonic signature from the two DACs is mostly cut from the same cloth, and not all that far apart. Since both Ken Redmond and Howard Milstein reviewed various versions of both the Mystique X and the Mystique Y DACs, I suggest also going back and reading their described comparisons between the two.

To my ears, the Mystique Y AM displays a dense, natural, organic flavor that is similar to the five other Mojo Audio DACs I have owned.  The presentation supports the perception of how music sounds in real life, with vibrant tonal colors, engaging dynamics, and strong bass.  The melodies are smooth, and the harmonics are balanced.  The soundstage is not overblown or underdone, although it doesn’t show quite the depth that I hear from the X SE NCZ.  The Mystique Y AM displays a sense of energy in the upper midrange and high frequencies that leads to a slightly sharper sound in comparison to my Mystique X SE NCZ, from which I perceive a rounder, more physical sound with more body and musical flow, sweeter but less incisive high frequencies, and maybe a bit more resolution. 

As much as I respect and enjoy what the Mystique Y brings to the table, and especially at its price, in my opinion, the Mystique X SE NCZ is the current Mojo Audio flagship for a reason.  In addition to the sonic attributes described above, hearing music from the X SE NCZ gave me a superior perception of ambience, of where the music was created and what is going on around the musicians, and greater physical depth.  The Mystique Y AM provides those positive attributes too, just not to the same extent as the X SE NCZ.  This is not faint praise when you consider that I have preferred the sound of the X SE NCZ over some pretty good DACs like the Mola Mola Tambaqui, the Merason DAC1 MkII, and Mojo Audio’s own well-reviewed EVO PRO.

How much are the differences I hear between the X SE and the Y related to the implementation of the different DAC chips used in the two converters?  I can’t answer that – you need to ask Benjamin.  However, other than the chips and inputs, the two DACs apparently share most of the same construction features and parts.  Therefore, as I understand it, there is not much else to be different.  As others have reported, the two chips do apparently each have their own unique sonic signature.  Also, maybe having a separate AD1862 chip for each channel (in the Mystique X SE NCZ) is beneficial in some way over using a single AD1865 stereo chip (in the Mystique Y AM), but again, you need to ask Benjamin.  I cannot answer why I hear differences between the two DACs, but I do know the (over twice as expensive) X SE NCZ provides more of the type of sound I enjoy in my system.

The good news is that the two DACs clearly represent the Mojo Audio house sound.   While I believe the differences between the Mystique Y AM and the X SE NCZ are perceptible in a resolving system, in many systems the differences I have described would likely be considered different shades of the same color.  In those systems, listeners would likely need to have both DACs in their system at the same time to reliably distinguish how they are different. 

I suggest looking at it like this - If you want a natural sounding DAC that enjoyably brings your reproduced music to life, try a Mojo Audio DAC.  If you want one of the most enjoyable NOS R2R DACs available, look at the Mystique X SE in whatever variant you can afford.  If you don’t have quite that much to spend, consider a version of the Mystique Y and enjoy that you are getting more than a taste of Mojo Audio’s top DAC for a much lower price.

Comparisons to Other Manufacturer’s DACs:

I have a few comparative DACs here in the general price range, including my SMc Audio DAC2 GT-24 (around $6K), a Metrum Acoustics Jade (around $3K), and a Benchmark DAC3 HGC (around $2,400). Two I would have liked to directly compare are the Linear Tube Audio LTA Aero (around $4K) and the Merason DAC1 MkII ($8,500) but, unfortunately, those last two have been gone from my DAC garage for months now.

The Jade is an R2R DAC while the Benchmark uses the delta-sigma conversion architecture so there are basic differences between those two similarly priced DACs.  Both of them are clean and articulate sounding in my system. However, what I hear from the Mystique Y AM is a more natural, realistic type sound than what I hear from either the Jade or the Benchmark, based on the Mojo DAC’s greater tonal color and dynamics.  In my opinion, the Jade is a bit more musical than the Benchmark, which can tend toward “clinical” sounding.  Based on my sonic tastes, I would choose the Mystique Y AM over either the Jade or the Benchmark.

I wish I still had the LTA Aero DAC here since buyers in the $4-$6K price range may be looking at both the overachieving Aero and the Mystique Y.  Being biased toward the Mojo Audio house sound, and comparing what I hear from the Mystique Y AM with my recollection of how the LTA Aero sounded in my system, I suspect out of those two I would personally choose the Mystique Y.  However, I can certainly understand some buyers choosing the LTA Aero, as I remember being impressed by the clarity and dynamics I heard from the Aero, as I reported in my write-up earlier in this thread where I said it provides a “vivid presence and a dynamic sense of realism.” 

I would strongly suggest buyers looking at the Aero also look at the Mystique Y, in whatever configuration they can afford since they are both strong choices.  However, I suspect the sonic differences between the Aero and the Mystique Y will result in buyers having a clear preference for one over the other, rather than it being a tight choice between the two.  While I would choose the Mystique Y, they both sounded good in my system and either choice would be a win.  Also, remember that both manufacturers offer buyers liberal trial/return periods of 45-days for Mojo Audio and 30-days for Linear Tube Audio, so there is no reason not to have the DAC that sounds best in your system.

I still own the SMc Audio DAC2 GT-24 with its CS4328 chip (“good odnobitnik” according to SoundBsessive).  Since the DAC2 is a delta-sigma DAC, the comparison to the Mystique Y AM is sort of apples to oranges.  The SMc DAC plays a bit smoother and a little more open sounding than the R2R DACs but slightly less organic, dense, and natural sounding, not unlike other delta-sigma DACs I have heard.  It doesn’t quite display the smooth, refined, analog-like sound that the Merason DAC1 MkII did when it was here, but the SMc DAC2 is actually more engaging to me based on its good drive, body, and tonal color.  A choice between the SMC DAC2 and the Y AM would be a close call for me and would require me to spend more time with each.

Wrap: To close, the Mystique Y AM DAC is another winner for Benjamin, and for Mojo Audio.  It is a naturally musical sounding DAC that compares well with other DACs in the $5-6K price range, and above.  It displays the Mojo Audio house sound with hard-hitting bass, a rich midrange, smooth treble and big macro dynamics, all leading toward an organically dense, natural, and engaging sonic treat at the price point.  In my opinion, the Mystique Y AM gives you about 85-90 percent of the sound of Mojo Audio’s current flagship, the Mystique X SE NCZ, that sits at a much higher price point.  The NC version of the Mystique Y may be even closer, but I didn’t get to hear that version.

Postscript Stuff:

(If details and fine print aren’t your thing, here would be a good place to stop.)

RCA/XLR Outputs and Cables: Benjamin has discussed that some of his customers believe the Mojo Audio DACs sound better from their single-ended (RCA) outputs. Fortunately, I was able to accommodate that configuration in my system by first trying the Mystique Y AM using single-ended cables extending all the way through my system, from the Y AM DAC output to the inputs of my SMc Audio monoblock amplifiers. I was not won over with the sound I heard through the single-ended connections. Later, I tried using single-ended cables only from the outputs of the Mystique Y AM DAC to the inputs of my volume control/preamp and then using balanced (XLR) cables for the remainder of the journey from the SMc preamp into the SMc monoblocks.  What I heard, aligned with my previous experiences, and with the feedback I have received from SMc Audio, that the SMc Audio preamp to amplifier connection sounds best using balanced connections. 

My initial impression was that using the single-ended (RCA) outputs of the Y AM DAC may have sounded a bit smoother and more relaxed, but I eventually decided I was hearing a dulling down of the sound when using single-ended connections.  In my system, and to my ears, using the RCA outputs resulted in the musical presentation having less tonal color and vibrancy. I was careful to level-match since using the single-ended outputs lowered the output voltage but, even then, reconnecting balanced cables to the outputs from the Y AM DAC restored a more vibrant and tonally rich sonic signature.  I heard basically the same thing when trying my X SE NCZ DAC from its single-ended outputs.

I suspect some of Benjamin’s customers do in fact hear good things from the RCA outputs of his DACs. Unfortunately, it just doesn’t work that way in my system and this recent experience reconfirmed that my system simply sounds better when played through the balanced connections. What I hear is likely related to the design of my other components and shouldn’t be used as a benchmark to judge how the Mystique Y DAC will sound in every system. To be thorough, I tried several different XLR (and RCA) cables out of the Mystique Y AM DAC, which confirmed my preference for the balanced outputs. 

Of the cables I have on-hand, Cardas Golden Reference XLR cables ended up as my favorites to use with the Mystique Y AM.  They seemed to display the best body and tone, as well as deep bass, and they rounded the sound just a little.  Conversely, through the Mystique X SE NCZ, the Cardas interconnects resulted in a presentation that was a little too dull compared with other balanced interconnects I have here. When selecting connections, the design of the individual components will affect how things sound when they are connected together.  Cable choices, and the balanced/single-ended issue I encountered is certainly not a one-size fits all proposition.

Is One USB Input Enough: I have played with DAC inputs quite a bit over the past 6 months. As a baseline, my Sonore Signature Rendu SE Deluxe (optical) streamer only has one (USB) output. I worked around that by adding a Singxer SU-6 DDC that allowed me to input the USB from the Sonore streamer into the DDC and then use multiple output options including AES/EBU, RCA, Toslink, or I2S (although I didn’t use I2S since none of the DACs on-hand had I2S inputs). 

After comparing most of the DACs involved in the earlier part of this thread, and completing my write-ups on those DACs, I began solely using the USB output of my streamer into the X SE NCZ DAC and later into the Mystique Y AM after that DAC arrived. I then added a Singxer UIP-1 PRO USB Interface to isolate the USB signal. Amir Majidimehr at Audio Science Review (ASR) reviewed the UIP-1 and concluded that it actually improved measurements when connected to certain gear, had little to no effect on other gear and, for most components, it probably isn’t necessary (not unlike most USB “decrapifiers”).  In my system, I don’t reliably hear any differences, so it probably isn’t necessary but since it doesn’t seem to do anything wrong, I keep it plugged in. 

In my system, I believe the USB input into my X SE NCZ sounds best. I use the Network Acoustics Muon USB cable. That the USB input sounds best is obviously convenient since I have a streamer with only one (USB) output. However, of all the DACs I have owned, the ones that had USB inputs seemed to sound best that way, or at least as good as they sounded through the other inputs, including I2S. Therefore, I would be fine if Benjamin could improve the sound, and reduce the cost, of his upcoming Z DAC by having only one (USB) input. Maybe offer other inputs by special order?

My System:  My reference system for purposes of listening to the Mystique Y AM DAC is as outlined below and as posted on my Audiogon virtual system page.  Racks and supports are either by Sound Anchors or consist of heavily reinforced wood furniture.  Support platforms consist of either hardwood, constrained layer materials (i.e., Zoethecus Z-slabs), a carbon fiber BDR Shelf (under the DAC), and Silent Running Audio Ohio-Class XL+ bases under the amplifiers.  Footers mostly consist of platinum silicone hemispheres sized for the weight of the components or speakers being supported.  Cables are a variety of what I have found to sound best, including Cardas Golden Cross speaker cables, and interconnects ranging from Cardas Golden Reference to Furutech PCOCC, to Belden or DIY tinned copper cables.  Power cords are by Isoclean, Furutech, Neotech, and DIY using Western Electric wire.  The components are as follows:

• sonicTransporter i9 music server (located in a network room away from my system)
• Silent Angel Bonn N8 Ethernet switch and Sonore opticalModule Deluxe (to convert Ethernet cabling to an optical cable connected with the following streamer)
• Sonore Signature Rendu SE Deluxe (optical) streamer
• Singxer UIP-1 PRO USB Interface
• Mystique Y AM or Mystique X SE NCZ DAC
• Hattor Big Preamp (in passive mode, for purposes of volume control and display)
• SMc Audio TLC Signature Edition Preamp (operated as a unity-gain buffer, with volume control removed)
• SMc Audio DNA-1 Ultra G20 Monoblocks (650 wpc per side)
• Aerial LR5 Speakers
• Aerial SW-12 Subwoofers (2 ea.)

Disclaimer (the fine print):  The purpose of this thread was to provide one person’s perspective when comparing a variety of DACs in a relatively stable system.  These writings are nothing more than biased observations and opinions by a hobbyist, and certainly should not be taken as a prediction or guarantee of how something will sound to another listener in their unique system with their unique music and listening preferences. To readers who plan to use the information from this thread to influence buying decisions, I strongly encourage you to also read other reviews and forum posts regarding the components you are interested in.  Consider how the reviewer’s systems and listening preferences are similar and/or different from your own.

Before you purchase a component, contact the seller to discuss any questions related to the technical design and construction, physical condition, and quality/estimated longevity of the component being considered. Inquire about, and obtain, the permissions and stipulations for a listening trial, if possible.  Returning a component that doesn’t suit you, or your system, even at a monetary loss of the cost of shipping and restocking, is better than feeling stuck with something you don’t want. 

Once you receive your new component, be sure to give it time to warm up properly, give yourself time to acclimate to the sound of the new component, and try a few different things (cables, power, tweaks, etc.) to make sure you are hearing the component at its best in your system.  After a week or so, try putting your previous component back in your system before making any final decisions.

I look forward to hearing the Mystique Z with the PCM58 DAC chips based on my fond memories of the sound of a Lector CDP-7T/Mk II that I owned.  The Mk II used BB PCM63 DAC chips while the CDP-7T/Mk III that I upgraded to used BB PCM1704 DAC chips.  I posted this way back in 2008:

"The only difference from MkII to MkIII was changing the DAC board to accomodate the BB PCM-1704 24-bit chipset instead of the PCM-63 20-bit chipset. I have been told by two people who should have pretty good ears that they believe the MkII sounds better than the MkIII. I have been told by more people that the MkIII sounds better. HP from TAS implied the MkIII sounded better to him. My ears tell me they both sound great, and not so different from each other. The MkII projects a "creamier" slightly richer, fuller sound. The MkIII has better resolution and also falls on the rich, full side of the sonic scale compared to many others, but slightly less so compared to the MkII. I believe the bass is tighter with the MkIII, and also just as deep and powerful." 

If you remember, many of us were chasing resolution back in those days, which is probably why I stupidly upgraded from the Mk II to the Mk III.  I remember the guy who purchased my Mk II was an experienced audiophile and I believe an industry insider.  He was thrilled to get the Mk II with its PCM 63 chips.  I remember thinking that he may know something I didn't, and I was right!

While I look forward to hearing the Mystique Z, the one I am most interested in hearing is the EVO DAC with the PCM63 DAC chips that Benjamin has proposed to release in 2027.  I suspect that could be the one that will make me forget about my EVO Pro.  

Have another comparison currently in process with an Aries Cerat Helene DAC.  Must say, this one requires consideration during set-up and I doubt I am done yet. Not the least of the considerations are the size and weight - the thing weighs 88 pounds!  It has three tubes and a user adjustable bias that does indeed change the presentation.  Cables matter too since it is really a single-ended unit and is said to sound best with single-ended output cables.

All I can say for now is that IMO this is a real contender in my system.  I am not surprised that it doesn't totally change the sound of my system compared to other DACs I have had here, but it does do some things very nicely.  Here are a couple of links to additional information (link 1) and some great pictures (link 2).

@brbrock  – over on the “What does your DAC sound like” thread, you asked:

"Although you said that the Helene is better can you tell me if the Mystique X SE sounds similar?"

Sorry for the late response, but it has been a busy time for me between trying to put some miles on my bicycle while also dealing with a new (to us) one year-old husky-shepherd puppy.  We have owned 6 huskies over the years, so this is not our first rodeo, but she is a rescue dog and has incredible energy while also requiring a lot of time for acclimation and discipline.

I haven’t posted too much about the Helene yet because I want to be as accurate as possible, and particularly when making any comparisons between it and the Mystique X SE NCZ, which I still own.  However, since you asked, I decided to post my answer here on this thread, where I will be posting further thoughts about the Helene when I am able.

I was not thrilled to have tubes in my system again as I have enjoyed the simplicity of leaving my system powered up all the time, which best matches my sporadic listening schedule.  It also seems that invariably, the best sounding tubes are expensive, hard-to-find, NOS types. I currently have three DACs connected through my Singxer SU6 DDC so I sometimes listen to one of the SS DACs when the Helene is still warming up, which doesn’t take too long.  It took me a while to dial-in different aspects of the Helene, including supports/damping, the specific tubes (the Helene can use multiple tube types), and the tube bias which is user-adjustable and affects the sonic presentation. However, the efforts to get it sounding right are worth it.

In addition to the issues related to having tubes in my system again, there are a couple of ergonomic things I don’t like about the Helene.  The only power switch is located on the back of the DAC, which seems a bit dumb for a DAC that needs to be powered up and down every day.  There is a convenient switch on the top front corner of the DAC that selects optional double reclocking of the digital S/PDIF and AES inputs using the internal Super Clocks of the converter, so it should have been easy to include a conveniently accessible power switch at the same location.  The other thing I don’t understand is the need for the Helene to invert phase, which makes DAC comparisons more time-consuming since the speaker cables must be reversed at the amps when comparing the Helene with phase-correct DACs.  In fairness, once a user settles in with the Helene as their sole DAC, the phase inversion will not be an issue.

Finally, I was a bit side-tracked when I recently purchased Monarchy 22B DAC on a whim to use in my outdoor system.  The Monarchy 22B is a true balanced ladder DAC using a pair of Burr Brown PCM63P-K grade DAC chips.  In my main system, I was floored by how good it sounds, compared to DACs I have here at any price, even though I only paid a few hundred dollars for the Monarchy.  The tone, macro-dynamics, and bass are so good, I am considering performing a major upgrade to hopefully close the gap on the higher level of refinement I hear from both the Mystique X SE and the Helene.  I have enjoyed having it in my main system so much that it may not ever see the outdoor system.

As a brief insight into what I am hearing from the dialed-in Helene, IMO, it just sounds like beautiful music in pretty much every way we want our systems to sound, tone, dynamics, sound staging, clarity, bass impact, texture, and more.  In my system, it does this on all types of music from hard rockers to softer instrumentals, and all types of vocals.   I am not saying it is perfect, or that it would be an end-game DAC for everyone, or even for me, but, in my system it may very well reach a level of performance that begins to eclipse what my other components and room can keep pace with.  I still like the sound provided by my Mystique X SE NCZ and, for those who don’t want tubes, that DAC remains a very nice SS option.  I also very much look forward to hearing Benjamin’s Mystique Z, which he is designing around BB PCM58 DAC chips.  I will post more about the Helene and my comparative thoughts after I can spend more quality time with it.

@brbrock - It is my understanding that Mojo Audio does indeed make the one MSB fine-tune adjustment on the AD1862/65 chips they use, but needed the more sophisticated equipment to make the four MSB adjustments on BB PCM58 and PCM63 chips.