December 2022

Mojo Audio Mystique X SE Stereo DAC Review
One of the most musical, engaging, and flexible DACs I've heard at any price.
Review By Dr. Matthew Clott

  When Benjamin Zwickel of Mojo Audio asked me to review his updated Mystique X SE DAC I jumped at the chance. My last experience with his equipment represented some of the best performance at any price, much less the huge bang for the buck it was at around $10K (in fact, the DAC was named the Mystique Evo B4B). The X signifies Benjamin's next evolutionary advancement. The closest I can compare is the Porsche 911. Take a thing and focus on making that thing the best it can be, limited only by the technology and advancements of the time. Don't look left or right, just ahead; make that thing better and better over time. There is both logic, and elegance, in this design principle that has worked well for both Porsche and Mojo-Audio.

So Mojo Audio's Mystique X just Evo'd another generation. The X stands for "extruded chassis," which is their "new extruded aluminum chassis combined with advanced anti-resonance typologies significantly lowering mechanical resonance and thereby lowering the overall noise floor." The unit is narrow and deep and quite attractive in its simplicity. It is approximately 60% the size, 60% the weight, and roughly 60% the manufacturing cost. Coated in a black textured polymerized aluminum composite finish with Alodine (lower RFI and better polymer adhesion) base coat. The front panel has a large "Mystique X" machined into its surface and three small plastic buttons at the top center to select input. I immediately called Benjamin and criticized the "cheap plastic buttons."

He laughed and spent the next 20 minutes telling me about the R&D they did on finding, acquiring, building, and designing more attractive buttons just to end up right back at the 50,000-cycle-rated selection switches with black plastic button heads they had been using for years. They did recess them a bit more from the previous models to improve their appearance. He emphasized that they use a chassis polymerized aluminum finish with anti-resonance qualities instead of simple anodizing and "cheap" button heads on buttery smooth switches with 50,000 cycle longevity for one single reason.

"At Mojo Audio, form follows function... we're not going to degrade performance or durability for aesthetic improvements." The SE version I was sent adds custom anti-resonance treatments engineered to deaden unwanted resonances in the chassis, power supply, and circuit boards. As well as an ERS Paper advanced Graphene shielding barrier between the main capacitor bank and the sensitive signal path circuitry.

They moved to modular circuit boards which plug in to a new custom engineered toroidal power transformer. Where as previously they had been using multiple PCB mounted off-the-shelf power transformers to achieve the five independent power supplies, the PCB floated on Sorbothane standoffs, and a massive custom 0.25" thick ferrous shielding divider to protect the sensitive circuitry from radiant noise created by the power supply. In the X series all five power supplies are fed from one amazingly well shielded custom toroid.

Not only does it utilize the most sophisticated of intrinsic shielding between primary and secondary windings but the transformer is also epoxy filled and sitting on a custom die-cut .125" thick pad made from Herbie's Audio Labs Grungbuster sheeting to minimize any mechanical resonances. And it is wrapped in a massive iron external band blocking any radiation from affecting nearby circuitry.

Mojo Audio has been using thermistors instead of fuses to protect their power supplies since 2017, but in the new Mystique X they had the toroid manufacturer engineer and integrate custom thermistors mounted to the transformer core to cut off any AC input long before the core temperature reaches any level that could cause premature insulation failure. Benjamin insists that no fuse could sound this good or work this fast.

Benjamin beamed, "Our new custom power transformers utilize the most modern state-of-the-art technology: quieter, smaller, lighter, and safer than anything else we could have used. And a significant contributor to our Mystique X's incredibly low noise-floor."

He continued, "Another upgrade to the power supplies in our Mystique X is the Silicon Carbide SiC zero-recovery ultra-fast Shottkey diodes used to rectify each of our five independent power supplies. We have always used ultra-fast recovery diodes in our DACs but these are the fastest and lowest noise diodes manufactured today... another state-of-the-art modern component we combined with our 100-year-old LC choke-input power supplies and 40-year-old vintage R-2R DAC chips to achieve that natural and organic sound Mojo Audio has become famous for."

And he concluded, "The final factor in lowering our noise floor was using integrated PCB-mounted connectors to eliminate all the wires in the signal path. This is nothing new to the majority of manufacturers...it is simply how most modern electronics are manufactured, but this is a completely new direction for Mojo Audio. Our Mystique X represents us moving from limited production hand-built electronics built with off-the-shelf components / parts to nearly unlimited robotically manufactured circuit board production which combine the best of modern and vintage typologies. Currently Mojo Audio products are 100% hand-built, yet once the recent delays and shortages end, we are planning on transitioning some operations into robotic assembly."

Sorry, that's a lot of quotes. But I wanted to convey both the level of detail he described and the excitement with which it was conveyed. He is very proud of this new iteration!

Listening Notes
In many ways, this review is essentially a sequel to the last review. I would guess many will want to know the differences so I will use the same songs to comment on again....

As an evolution of the previous DAC, everything I heard and reported previously is still there, but more mature. It still sounds organic. It still sounds Natural. It still sounds like music. The detail and resolution are all still there. Pace and rhythm, high-frequency extension, low-end oomph, soundscape depth, image density, and localization? Ummm, yes and yes, wow, woah, so very deep, palpable, and overwhelmingly realistic. Mojo Audio's Mystique X SE sounds even less digital than the previous generation; and dragged me further from reviewer mode and shoved me, unforgiving, into listening mode.

Hugh Masekela's Coal Train (Stimela) (on Jive Africa JVD-0330B in 16-bit/44.1kHz) or Shelby Lynn's "You Don't Have to Say you Love Me" (Just a Little Lovin' on Lost Highway Records 24-bit/192kHz lossless FLAC) again, I'd be just fine with that. BUT, the familiarity I have developed with these tracks makes them as reliable and necessary for delineating subtle difference in components as a chemist using standard solutions in their lab. With that being said, I got smoke in my eyes while listening to Hugh and that cowbell sounded about as real as I've ever heard it sound. The drum kit was wide, deep, realistically conveyed and punched me in the gut.

And that sexy saxophone floated in the air and had that resolving brassy bite that makes you think vinyl, not digital. Mussorgsky’s Dance of the Persian Slaves (Khovanshchina, Act IV, Pentatone, FLAC 96kHz/24bit) is a reliable scaling tool and the X SE scaled like a rock climber rocketing up the side of an indoor climbing wall. It also painted a symphonic image with realistic width, depth and height.

Yellow's "Out Of Dawn" (Touch Yellow album on Polydor 0602527194851 in16-bit/44.1kHz) grabbed and held me just at it had before, but there was a more visceral presentation than the last time as a result of a blacker background and tighter grip on the image and instrument density.  I felt this track more than last time, both physically and emotionally.

Billie Eilish's Don't Smile At Me [Darkroom 7799202 at 16-bit/44.1kHz) is just a terrific track. Forget the audiophile speak. Just listen to it. Sometimes the non-audiophile tracks are the best to evaluate. Billie and their sibling engineer this track with a heavy weight on forward presentation and lateral presence. The Mystique X SE did a wonderful job of just getting out of the way and letting what was recorded show up magically in my room. This track, more than any other, gave hints as to how well this DAC just does what it is supposed to and avoids doing what it shouldn't do.

Finally, Bruno Coulais's soundtrack Himalaya: Rearing Of A Chief has a track titled Norbu (Peermusic France 030206718928 in 44.1kHz/16-bit) that has this wonderful contradictory ethnic drumming alternating with a pure native string instrument plucking, and an overlying haunting chant. The piece is beautiful, deep, eerie and mesmerizing and you should add it to your listening list right now. Those drum pulses alternate between impactful and visceral, and the X SE gave me not only what I wanted, but what the song offered.

The backgrounds were black and deep, the deep strikes conveyed proper texture and I could feel the vibration and impulses conveyed by each mallet striking the drums massive animal skin. The plucking was clean and clear with fast and true leading and trailing edges. Like the other pieces, when I go through the entire track and enjoy what it has to offer instead of looking at my listening list to see what’s next, I know I’m in my audiophile happy place.

What Benjamin has accomplished with this DAC is a level of performance value that I have not heard previously. Unless you have a system of massive cost and incredible performance/resolution, this Mystique X SE will likely be all you ever need or want.

A Few Questions
I asked Benjamin to tell me how he achieved that soul and heart in a product I consider to be well within the very affordable class for what this DAC achieves. And then I asked him to share what he considered the secret sauce of Mojo-Audio.

Here Are His Answers
As for the "soulful connection" to the music, that is the time, tune, and harmonic coherency I'm always talking about. in my experience, to have that organic character a DAC has to be more resolving, faster, etc.

What some critics of my DACs call a "blending in" sound is what I call being harmonically coherent and in proper time and tune. In other words a general effortlessness where nothing draws attention to itself or stands out.

What do I think is the secret sauce of our Mystique DACs?

So any DAC with a capacitive power supply (pretty much nearly all DACs), no matter how good or how much capacitance they have, can only store voltage. As a result, the energy of the music is always in a state of becoming. The more energy a note requires, the more off time and tune it is from all other notes. A capacitive design will always sound off time and tune when compared to our Mystique which has a choke input analog power supplies which stores both current as well as voltage.

Our choke input power supplies give instantaneous unrestricted bursts of energy...no undershoot or overshoot.

Conclusion
Looking back, I concluded my previous Mojo review as follows, "The Mojo Mystique Evo B4B 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." 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.

I can say with all sincerity that if someone took away my reference DACs (which are each four times as expensive as the X) and I was told I have to live with (and use for reviews) the Mojo Audio Mystique X SE stereo DAC for the rest of my days, I would be just fine with that. And there might even be a tiny little part of my brain that smiles and whispers, "YES!"

Specifications
Type: Hi-Res Audio digital to analog converter
Frequency Response: 20Hz to 50 kHz (+/-0.5dB)
Chipset: Analog Devices AD1862 R-2R ladder DAC
Converts PCM format files up to 24-bit/192kHz via USB, S/PDIF coax, and AES/EBU.
Direct-coupled ultra-high-performance Staccato Class A discrete OpAmps.
Independent circuits optimize linearity for L and R channels
Cryo'd Kimber Kable VSS VariStrand wire
Furutech rhodium plated low mass RCA connectors
Neutrik gold plated male and female XLR connectors
Ground lift switch to isolate DC signal ground from Earth, chassis, and AC grounds.
USB lift switch to optimize S/PDIF inputs and eliminate clocking noise.
Three-point Herbie's Audio Lab Fat Dot anti-resonance footers.
Low-resonance high-rigidity extruded aluminum chassis.
Field convertible from 110VAC to 250VAC both 50Hz and 60Hz.
Dimensions: 9" x 4" x 16" (WxHxD)
Weight: 19 lbs.
Price: Starting at $7,999, with upgrades $9,999 as reviewed

Company Information
Mojo Audio Inc
12941 Marva Place SE
Albuquerque, New Mexico 87123

Voice: (949) 438-6656
E-mail: info@mojo-audio.com 
Website: Mojo-Audio.com