Massdrop x Airist Audio R-2R DAC - Review

massdrop
airist-audio

#1

Massdrop x Airist Audio R-2R DAC

About a year ago I was approached to provide some early feedback on a new multi-bit (discrete R-2R) DAC. It didn’t have a case. It didn’t have a projected price. It didn’t have a release date. And it didn’t have a name - simply being referred to as “RDAC”.

First impressions were distinctly positive, even compared to some of the stalwarts in this space, to the point I was quite anxious both to learn what it might be sold for and to hear how the final iteration was going to perform. So, when about a month ago I was offered a unit with the final production electronics, properly cased, and ready to be subjected to a formal review, I jumped at it.

Today the veil comes off and what is now officially called the “Massdrop x Airist Audio R-2R DAC” (or, “RDAC” for short) is public and being formally offered for sale, at $349.99, starting on June 6th:

I’ll cover the basics of the unit, and how it sounds, in this post and add some basic specific comparisons to other DACs, technical details and pairing with a few amps in subsequent ones.

Major Features

The interesting features of the RDAC are buried inside the unit - the exterior being an unassuming, but stylish matte-black housed in a chassis that stacks perfectly with the Massdrop x series Cavalli amplifiers:

  • Dual 24-bit discrete R-2R ladders, per channel, in sign-magnitude configuration.
  • Bit-level buffering/isolation on the ladder resistors.
  • Separate PCBs for the resistor ladders vs. I/O, conversion and other processing.
  • Internal power regulation and reference voltage stabilization.
  • Low phase-noise NDK clocks.
  • Custom decoding and linear-phase filter implementations.
  • USB (galvanically isolated) and S/PDIF (COAX and TOSLink) inputs.
  • PCM native conversion up to 24 bit/384 kHz.
  • DSD support to DSD128 (via internal PCM conversion).

How Does it Sound?

The TL;DR; here is simply that the RDAC sounds marvelous .

The signature is one of general neutrality with a touch of sweetness to the mid-range and upper registers, and a distinctly “pristine” quality/clarity to the sound. Overall presentation is open with a good sense of air but is neither lacking, nor carrying too much, tonal weight/density. The RDAC’s rendering is fluid, articulate, nuanced and well balanced - capable of excellent top-end delicacy while simultaneously plumbing a tuneful, driving, bass-line and keeping vocals present and lucid.

The strongest, and most enduring, comparison I can make for the Massdrop x Airist Audio R-2R DAC is that, at least from a signature perspective, it sounds like a Holo Audio Spring DAC and Soekris dac1541 got it on - and this was the result. It exhibits some of the sweetness that I found so beguiling with the Spring DAC combined with the distinctly “pristine” quality to the sound rendered by the dac1541.

While the RDAC is not quite on the same level with all technicalities as those two units, it’s surprisingly close and the combination of their better sonic aspects results in a very compelling delivery with a broad variety of music.

In More Detail

Tone is lovely and pure, with just a hint of sweetness. I’d stop short of calling the presentation romantic or euphonic. There’s just enough “sugar” to keep the otherwise “pristine” or “super clear/resolving” delivery on the “musical side” of things vs. drifting off towards being “analytical” and is, for me, a more engaging listen because of it.

Extended sustain on piano notes, from my own pieces, exhibit none of the strange tremolo or vibrato that I’ve found in some other discrete R-2R DACs that would be considered natural competitors to the RDAC. Here … the tone remains pure until the notes naturally ebb away.

Timbre is natural and realistic. Instruments are easy to identify reliably, even in very complex orchestral works and when they’re separated by relatively minor familial differences, purely by how they sound (without resorting to locational cues). Individual oices, similarly, are easy to identify and localize, even when faced with multi-part close-harmonies.

Transient performance is excellent, almost NOS-like in fact, with plucked strings, discordant brass and aggressive percussion all exhibiting surprisingly rapid and impactful attack/bite. Switching to electronic music and the impact and transient speed remains … play the first 60 seconds of “The Rat” (Infected Mushroom, “Army of Mushrooms”) and you’ll see what I mean. Or run something like “Along this Road: Kono Michi” (Ottmar Liebert, “One Guitar”) and the instant bite of the pluck and the reverberant decay against a deep, dark background.

As I’ve said, there’s a hint of sweetness to the delivery of the Airist Audio R-2R DAC - and this is most in evidence in the mid-range. Lucid and transparent are also terms that come immediately to mind here. Vocals, particularly female, are present, well articulated, and unexaggerated. There’s no apparent emphasis or reticence. Just a natural, emotive, and evocative rendering.

Something like “Ellis Island” (Mary Black, “Looking Back”) showcases this sweetness quite nicely. And being a semi-sweet piece in its own right helps to show when this sort of sound is taken too far … and with the RDAC it is not - it’s just where I like it.

The upper registers are clean, smooth and properly extended, carrying some of that mid-range sweetness forward in a Goldilocks-like “Aaahh … just right” fashion. There’s a palpable sense of air and space and a very honest delivery. If there’s sibilance or harshness in the source material it’ll be reproduced faithfully, without ever exaggerating or exacerbating it. Cranking various pieces by “Heart” or “Julia Fordham” can be a bit of a wince-inducing torture test in this regard but were handled with aplomb by the RDAC.

Playing a couple of “guilty pleasure” tracks here, specifically, “Buffalo Girls” and “Double Dutch” (Malcom McLaren, “Duck Rock”), through the RDAC shows that it is not going to gloss over faults or harshness in a recording (and you can hear well into the aggressive edits/mix of, say, some of Prince’s works) but it won’t make them worse either!

At the opposite extreme, the bottom octaves, while perhaps not the absolute last-word in terms of low-end drive and slam, are only marginally behind the front-runners there and the RDAC certainly isn’t lacking in the bass-department. Playing some more bass-intensive tracks (Beyoncé’s “Partition” or Trentemøller’s “Chameleon”) shows no lack of weight, and excellent texture, speed and articulation. A run through Talvin Singh’s collection “Anokha: Sounds of the Asian Underground” is, similarly, fully satisfying.

Stage is quite convincing. I only got to test this with headphones but even so the RDAC is capable of projecting a realistically wide stage, and the “sense” of space in a given venue is very well communicated - play something like “Mining for Gold” (Cowboy Junkies, “The Trinity Session”) and you’ll be subjected to a distinct sense of the simple, stark, natural environment the recording was made in.

Layering and separation are typically strong points of R-2R implementations for me, and the Airist Audio R-2R DAC is no exception. Picking out individual instruments in a complex mix is easy as is tracking the melody while tapping your foot along to the baseline (which you’ll be hard pressed not to do).

As mentioned initially, there’s a distinctly “pristine” aspect, and a strong impression of “clarity” and resolution/detail that’s evident even on first listening to the RDAC. There’s nothing artificial to this … the detail is real and not of the often-encountered “artificial hyper-detail” found in many D/S type converters. Brushes on cymbals or drum skins, decaying triangle strikes, and so on exhibit are resolved to a level that I’ve generally only found on rather more expensive units.

Dynamics, both macro and micro, are addictive. “Sledgehammer” (Peter Gabriel) or the intro to “Twist in my Sobriety” (Tanita Tikaram), which are possibly opposite extremes, still both provide graphic illustrations of the ability of the RDAC to simultaneously handle large dynamics while maintaining deftness, subtely, and resolving power with micro-dynamics. Cohen’s typically gravelly delivery, perhaps exemplified in “You Want it Darker”, also serves as an excellent illustration of the Massdrop R-2R DAC’s ability to portray tiny, subtle, variations in volume modulation … which gives his voice a lot of its visceral emotion.

All of this is set against a deep, dark, velvety-black backdrop. There’s no sense of veil here. Clarity is excellent and, again, “pristine”. Noise on the recording, be it from the tape, the environment (in acoustic recordings), and so on will be fully reproduced, but nothing is getting added to it. I think this is, as with a couple of other DACs I’ve listened to recently, a major factor in how pronouncedly some of the other positive traits are rendered.

The RDAC Should be on your RADAR if You’re-Shopping-For:

If you’re in the market for a DAC and have been considering the Schiit Modi MB or Bifrost MB, Soekris dac1321, iFi Audio Micro iDSD Black Label, Chord Mojo, or DENAFRIPS Ares, then you should add this to your list of units to audition/consider.

In real terms, it wasn’t until I got to the level of the RME ADI-2 DAC and the Soekris dac1421, both coming in at around $1,000, that I could say that I found something that was, across the board, better technically than the RDAC while being as enjoyable to listen to (I do still like the hint of “sweetness” from the RDAC, however).

[You should also note that those units give a slightly false sense of the level of price/performance on offer here as they include other features, including capable headphone outputs and, with the RME unit, a very rich EQ and DSP capability.]

Summary

The Massdrop x Airist Audio R-2R DAC is an excellent sounding DAC, with a slightly sweet tone, a distinctly “pristine” and clear delivery and offering very high value. In the month I’ve been listening to it, it has been unfailingly engaging and involving, while continuing to impress on technicalities.

For the $349.99 asking price, the RDAC is an easy and enthusiastic recommendation.

Compared to its primary competition, and some units that could reasonably, at least on a price basis, be considered one or two tiers above it, the RDAC offers both higher value and, for me, both better performance and a more enjoyable overall listen. As such I expect it’s going to prove to be somewhat disruptive in the sub-$800 DAC ($1,000 DAC/amp) market.

Some of that has to be attributable to the Massdrop design and manufacturing approach, which clearly enables higher than expected performance at lower than typical cost.

You can be sure that I’ll be joining the drop when it goes live on 6/6.


DAC/AMP Upgrades and Sidegrades Discussion
Massdrop x Airist Audio R-2R DAC - Review & Impressions Index
Campfire Audio Cascade Closed-Back Headphones - Official Thread
#2

Great write up! I have a few follow up questions:

  1. Can you suggest some tracks that benefit from the “sweetness”? Some that don’t?
  2. What kind of amp + headphone combo do you need to be able to realistically tell the difference between this and the ADI-2 or Soekris dac1421? Can you hear the difference on an HD600/650? DT1990? Or will you need headphones in the $1000+ tier to be able to tell the difference? Same with Amps. Another way to put this is… at what tier of headphone does the RDAC become the limiting factor in the chain?
  3. “If you currently own —X--- DAC, the RDAC will be a noticeable upgrade.” What can X be filled with?
  4. Would love some comparisions, especially with iFi iDSD BL, Mojo, Topping D50, Modi MB, etc.

Thanks again for taking the time to write this!


Holo Audio CYAN DAC/Amp - Official Thread
#3

Damn it, I just got a line on a Audeze Deckard for the same price… I will definitely be joining this drop. Great write up…now to decide on the Deckard…To Deckard or not to Deckard lol


#4

Excellent write-up @Torq!

I am also curious to hear your comparisons. I know you have some pretty good experience with a variety of DACs across various price ranges. Specifically against the Mojo and iDSD Black Label.

Which amp was your favourite to pair with it?


#5

More reviews here:


#6

Personally I like that hint of “sweetness” (I go on about it quite a bit, but it is a hint … and not on the level that people might expect if they read “sweet” and thinks “tube euphonic”) with pretty much everything. It’ll be more in evidence with music that isn’t poorly recorded/mastered or isn’t overpowering harsh to being with.

Mellow and moderately brighter female vocals, simple and/or solo strings, especially plucked, will probably be the best bet to be able clearly hear the effect vs. other DACs, if you’re not sure what I’m talking about.

I’ll see about coming up with more specific examples though.

Absolutely the HD6XX are enough to tell the difference between the RDAC, RME and Soekris units.

To do that comparison I’d personally want to run both the ADI-2 DAC and the dac1412 into an external amplifier, since I think in both cases their internal amplifiers holds the DAC-sections back.

Nothing exotic is required … the fundamental signature differences were quite apparent even on $100 - $250 amplification. Some of the subtler/more nuanced technical differences require something a bit more resolving.

More resolving/capable transducers (and, of course, amplifiers) will certainly make it easier to hear the differences between any two sources. And if the differences in, say, micro-dynamic resolution of the source is below the threshold your headphones can reproduce, that aspect wouldn’t be audible (for better or worse). Similarly, if DAC or amp “A” has a transient response better than your headphones, then DAC or amp “B”, could be even better still and you’d never know until you switched to a more capable transducer.

So, no, $1,000+ cans are not necessary to hear these differences (though some may not be discernible with ALL headphones), and the HD6XX line is quite capable in this case.

Hard to say, since “tiers” of headphones are a rather blurry thing unless you go by price alone, and that’s a really unreliable basis for that type of comparison (especially with transducers). Nuances/improvements in some technicalities were still improving up to the HD800(S) at least (e.g. micro-dynamics and transient response).

Bear in mind that the “law of diminishing returns” takes effect extremely quickly with DACs. Differences are common. Definite improvements are harder to qualify.

But, say, in a system that was built on the RDAC then I wouldn’t feel bad about pairing with an amp like the Schiit Lyr 3 or iFi Pro iCAN, and headphones up to a couple of thousand dollars. I probably wouldn’t go quite that far as I prefer a bit more balance in my setups, but the “headphones should be the bulk of the budget” mantra generally holds true for me (until we get to serious exotica anyway).

For me everything in the list in the first post, and pretty much everything else I’ve heard up to the $800 or so mark (a bit more if we include AIO units). Bear in mind “upgrade” in this context means “I liked it better” which is an amalgamation of audible performance on various musical technicalities and how much I enjoyed listening to the thing (signature preference).

Your mileage may vary.

Not every technical element will be a clear upgrade in every case, and you may weight “bass quantity” (for a simple example) over “bass quality” which would result in us having different opinions - especially if that were your primary concern.

Whenever possible, I recommend auditioning anything you want to buy.

Excepting the Topping unit, those will come in a follow-up post in a bit. For reasons primarily related to the preservation of my enjoyment of this hobby, that’s one you’ll have to do for yourself.


#7

Sounds like an interesting product. Gotta love how much Massdrop is doing for the audio community.


#8

I’m probably always going to answer that question with “my big Woo” :wink:

I did find it had excellent synergy with the Massdrop x Cavalli Tube Hybrid (stacks properly with it too, of course), particularly into HD6XX and HD800(S). But the Pro iCAN (in any mode) and the Woo WA234 both showed it has more to give technically.

The slightly sweeter tone of the thing is going to make it a good pairing with a pretty broad array of solid-state amps, and it’s performance will mean you can take that quite a ways before having to start thinking about a DAC upgrade.


#9

Is your avoidance in reference to the D50 specifically (e.g., its components), Topping as a brand, etc?

For that matter, the FiiO Q5 is also in the same price range. And a wildly different product.


#10

I should probably convince @andrew to get our hands on the Cavalli Tube Hybrid at some point. They had a couple kicking around at CanJam SoCal this year but I don’t think we got the chance to actually hear any headphones through it.

We’ve got a variety of amps rotating through so we should probably get in on this drop for some A/B testing with some of the DACs in the office.

My wife is finally letting me build an office at our house so I’m starting to flesh out my desktop set-up. This seems to fit with my preferred sound pretty well!


#11

It’s specific to the D50.

Not because of it’s components, not because of the brand … but because I’ve heard it.


#12

I used to have my own office/game room… Then I had a kid… And now I listen to music in the dark and drink whiskey… Alone…

But seriously totally worth it, she is awesome! Still want to build a office/game room again, though! But with more of the audio background in mind… Some sound correction and what not.


#13

Comparisons to Other DACS

As promised, here are some basic comparisons that highlight the most significant deltas in terms of listening/technicality with the most likely candidates that’ll be shopped against the RDAC.

Schiit Modi MB (via USB) - $250

For a long time, my go-to reference for an “entry level” DAC has been Schiit’s Modi MB. I still think that it is an excellent unit. The RDAC offers a sweeter presentation, better resolution and clarity and a darker background compared to the baby-Schiit. The difference is enough that I think the RDAC is the better buy, despite it’s $100 higher price-point - if you can swing it, you should in my opinion. The Modi MB does offer a slightly more impactful bottom end, but the difference isn’t huge and is likely affected to a much greater degree based on amplifier pairing.

Schiit Modi MB (w/ Eitr) - $379

Adding an Eitr in the replay chain ahead of the Modi MB and driving it via COAX brings things a bit closer together, however I would still place the RDAC ahead - particularly when it comes to clarity, resolution and top-end air/space.

Chord Mojo - $549

While the Mojo has a slightly warmer signature, the Massdrop unit exhibits better bass texture and weight/slam combined with a notably smoother higher treble rendering. Raw resolution is similar in the mid-range, but I prefer the tone of the RDAC. And the Arisit Audio DAC conveys a better sense of air and the general ambience of the venue with the acoustic recordings I tried.

Bifrost MB (w/ USB Gen 5) - $599

Next to Bifrost MB, the RDAC continues to deliver a blacker background, the sweeter presentation and there’s still a slight sense of better clarity out of the RDAC. But now resolution and micro-dynamics are largely on par and the Schiit DAC’s low-end drive is still slightly superior. Again, not a big difference, but absolute bass-heads might prefer the Schiit unit - depending on what amp they’re pairing with.

iFi Audio Micro iDSD Black Label - $599

Not a perfect comparison, as the Micro iDSD BL is not just a DAC and, as such, presents interesting variations in perceived value based on how it’s going to be used. AS a pure DAC, however, the smoothness of the Micro iDSD seemed to take a little of the edge off brass and discordant piano (that’s a negative, as far as I’m concerned) compared to the Massdrop DAC.

The mid-range delivery between these two units is similar in terms of liquidity and resolution, though the “sweeter” delivery from the R-DAC works better for me without coming across as specifically romantic.

Bass is rounder and fuller out of the iFi unit, but this came at the cost of a slight loss of texture into the mid-bass vs. the RDAC. I’d say quantity favors the Micro iDSD and quality the RDAC.

DENAFRIPS Ares - $650

The Ares has slightly more weight in the bottom end than the RDAC, though perhaps not quite the Massdrop unit’s dexterity with a fast, multi-tracked bass line. Mid-range lacks the sweetness of the RDAC, which may or may not be a good thing for everyone. Transient response, particularly with plucked-strings and rapid percussion, favors the RDAC - as do both macro and micro-dynamics and raw resolution.


#14

Any chance you have an opinion on how it would compare to a SMSL M8?


#15

I take it your experience wasn’t so good?


#16

Thanks for going into such detail on this. It really does sound like a good DAC, and I’m wondering if I should join it too. I have the MCTH, so this should pair nicely!


#17

Not one based on actual listening, no.

I found the D50’s presentation to be sterile, clinical and analytical. Technically competent, but not something I wanted to spend more time listening to (and certainly not the amount of time it takes to review things properly).


What are you upgrading?
#18

There seems to be some possible intellectual property issues

Here are some initial measurements.

I was interested, but my enthusiasm is a bit dampened after reading these posts.


#19

I’m not going to be an early adopter for this one.

I’m mostly concerned about consistency and quality control with a technology that’s got a checkered history.

At times a clean/analytical DAC helps to work around other components. Stacking a colored DAC on my tube amp may be too much color for me. Some of my headphones are already warm/dark too – so I currently pair them with a clean DAC.

I’d love to demo this before buying.


#20

I’m sort of on the same boat there. I have the MCTH, and even though this stack looks amazing, I’m already quite happy with my D50, which is known to be quite transparent.