Audio-gd R2R 11 mkii review
A. Introduction
I recently received the new Audio-gd r2r11mkii. It was ordered directly from Audio-gd, in China.
The idea beind this new unit was to pack as much value in a new and improved version of the Audio-gd r2r 11 while keeping the price reasonably low, retaining the minimalist design ( short digital signal path, the DA-8 conversion boards receiving the signal as is, doing themselves only minimal digital sound processing, and no analog input) and keeping the same sound signature.
The reason for eliminating the original r2r 11 from Audio-gd's lineup was that it had been rendered not profitable by the recent chip crisis and the rising costs we can observe in our lives at this time. Raising its price would have made it less popular, and thus likely still not profitable.
At some point, i made a post on Headfi proposing to make a bigger and better r2r 11 selling for substantially more money but keeping the overall design and sonic identity intact. There were two main considerations on my part: to still keep an affordable r2r unit available and to prevent the death of what became a classic thoughout its 4 years of existence. In fact, Kingwa, the owner and chief designer of Audio-gd, sold a lot of these units. Most buyer as myself became huge fans of its organic and musical sound, which provided just the right blend of accuracy, warmth, dynamics and neutrality, and a good driving ability for moderatly difficult loads.
The main design point in the original design is that no powerful (expensive) chip was needed as only minimal digital processing was performed, and this allowed keeping the price low.
As i could observe myself, oversampling has benefits but also drawbacks. Using foobar with the original unit, i realized that when i activated oversampling using the best quality settings, some low level details were washed out of the sound. This was a big surprise to me. Of course, oversampling allows improving S/N for a 16-bit music files, and also allows enhanced dynamics, but there is a drawback in that the output can become less faithful and accurate to a certain extent. Many audio designers have for that reason tried other avenues to improve the digital signal as alternatives to classical oversampling. I never in fact used the unit with external oversampling after this.
What is remarkable about the sound of the r2r 11 is it is quiet, smooth and dynamic enough while remaining a non oversampling audio device. I wonder how Kingwa managed to create a unit selling for so little money while being captivating to listen to day in day out. Surely it has to do in part with the sound purity to which i just referred.
Time went by after i made the post on Headfi and then, weeks later, Kingwa, who is also a good friend, contacted me about the idea I had. We exchanged emails back and for and the new design came down to these elements:
- bigger chassis to allow a more elaborate device
- better power supplies, including a substantially bigger r-core (instead of a toroidal) transformer
- relay volume control
- improved output stage to enhance the sound quality further
- usb galvanic isolator to isolated from noisy computers and prevent ground loops
- Crystek clocks on the Amanero usb module
- integration of the latest ultra-low noise digital psus
- enhanced class a/b output stage
- remote control
The most amazing thing is that eight hours later, Kingwa had already drawn the pcb "by hand", not trusting software-produced layouts regarding sound quality. Kingwa works really fast, to say the least. I was really surprised and amazed.
And i can already tell you is that the vision of the product translated as is into the final result. The unit is as I though it would be, only a little bigger. Note that the unit remains a single-ended design, which helps a lot with pricing.
B. Unpacking, setup and burn-in
As usual for Audio-gd, the unit came in a cardboard, braced with protecting foams to prevent shocks. The unit was cosmetically perfect, and demonstrated a size a weight that made things clear about the substantial upgrade from the original. In fact, the size comparison is quite stunning. The dimensions went from W180 X L220 X H55 to W240 X L280 X H85, which means over 2.5x the volume. Fortunately, the length of the unit remains quite raisonnable at 280mm, while the weight went from 4 to nearly 8 pounds. As for presentation, think about a less deep NFB-28, without a balanced output. I would have hoped for a narrower unit but i was nonetheless able to fit the unit on my office desk, to the left of my diminutive power amplifier. The box also contained basic power and usb cables, and the free remote control, which looks cheap but feels good enough for a few years of intensive use. A high-quality aluminum remote is a 40$ option.
The rest of the test setup is quite modest: a small 70wpc power amplifier using a circuit inspired by a famous English brand i got for under 300$, and a set of affordable Chinese speakers, the Soundartist S5b, which i got for approximately the same amount, shipping included. The interconnect is a good-quality cable obtained from Ebay for about 20$. The usb cable is a dual-trunk design based on Sommer Cable wire that I got from a Chinese sellor in HK years ago. Finally, the speaker cables are made out of two runs of silver-plated multi-wire braids intended for heaphones, one such cable being used per speaker pole, for a total of 15awg. Given each speaker cable is only 4 feet long, this is sufficient in size.
My original setup with the original r2r 11 used a pair of usb cables instead, including a Supra, the other one being a silver cable worth 80$ on Ebay, allowing the addition of the standard version of the Intona usb isolator in between, and providing a welcome and unexpected sound quality upgrade. The rest of the setup was the same. As streamer, i use the Allo Usbrige with a good-quality linear power supply.
As headphones, which i use rarely while working, being alone in the house, i have the Blon B8 with Brainwaves sheepskin pads (much larger than the original) and the Aliexpress Music Master closebacks, also fitted with sheepskin pads, which make the sound smoother. I also tried the Music Master E1000s and Sony MDR-7506s in some tests.
I set the unit for a 10-day 24/7 burn-in driving the Music Master closed backs at average sound level (28 on high-gain mode). With the 100h done at the factory, this sums up to 340h. I do not believe the unit is fully burned-in at this point but it is close enough to make a fair review.
C. Presentation and sound
The first sonic impressions were of a quieter, smoother and more refined unit, well justifying the big price increase. In fact, i would argue that the new unit is an even better value than the original. Besides the free remote, everything looks and feels of high-quality. This is of course an old-school presentation, with a led screen and a big aluminium volume knob, and for my tastes, it's perfect. The headphone socket is sourced from Neutrik and features a locking mechanism whose button needs to be pushed quite hard to disconnect the headphone jack.
On the back, things are also simple. There is an on/off toggle integrated with the power cord socket, an rca SPDIF input, an optical SPDIF input, a usb input, in addition to a set of RCA connectors for the DAC/PRE output, exactly the same as the original r2r 11 offered. It is also worth mentioning that the unit can be set internally for either 120 or 240V operation. The unit is shipped according to destination at the factory.
So as burn-in progressed, there were some of the usual roller coaster effects in sound quality , which can be disconcerting for someone not used to it. However, from day 3 or 72h, most of the amplitude of these variations had vanished while soundstaging and bass depth continued to progressively develop.
Compared to the original, the impression is clearly of a higher end unit, with blacker background, smoother highs and better control of bass. And a more relaxed sound, be it on the MusicMaster E1000 headphones, the closed back Music Masters, the Blon B20 or the S5b loudspeakers. The driving capacity showed as improved as the unit did not loose any of its composure with the bigger and more demanding E1000 106mm planars. In all cases, the sound quality improved about equally. This seemed to indicate that the unit improved both as a dac and as a headphone amplifier.
To focus on the dac part, i brought in the very easy to drive Sony MDR-7506. The original drove them without any effort. The new unit still brought a smoothness improvement, which i attribute to the dac. This interpretation was confirmed by a similar conclusion using the s5b louspeakers.
As for the diving capacity improvment, it was shown by a better defined bass in the lower register, with also better bass extension using both planar sets.
As burn-in progressed, more air appeared around the instruments, making the sound even more refined and high-end. Also, the soundstage widened considerably and got deeper, to such an extent it became significantly better than the original. What is really important to mention though is the fact that the basic essence of the sound remains unchanged. It is still an organic sounding device, with good dynamics and bass, and accurate timbres. So it is a solid candidate from a budget-friendly upgrade to the original. In fact, I don't think there is much competition to this unit in its price range.
D- Compared to the R7he mkii as a dac
Now to determine what the unit is worth in the absolute, I thought of inserting it as a DAC in my main system (all Audio-gd), in replacement of the r2r 7 mkii. My setup is composed of a Usbridge Sig transport feeding a di20he, on to the r7he mkii, to the HE-9, to the Master-3, to the Osborn Eclipse loudspeakers. In addition, both the DAC and digital interface are clocked by an Afterdark Eva clock (top of the line). I had two configurations in mind:
1. The first would consist in feeding the r2r 11 mkii through the usb input, therefore putting the external clock and di20he aside.
2. The second would consist in feeding the r2r 11 mkii from the externally clocked di20he through its RCA SPDIF input.
With configuration #1
The r2r 11 mkii outputs a sound that is as analog as the r7he mkii used with the Afterdark Eva 10M clock, with more meat on the bone, this probably being in part an effect of the rather long rca cable used to hook it up to the HE-9. Besides the welcome meaty medium, the highs are also silky smooth.
On the other hand, attacks are not as sharp. The stage is not quite as wide or deep, nor is imaging as precise. But the result is notheless very musical, bass having a very good presence. The midrange is where the r2r 11 mkii excels. It is rich, and full of nuances. What i take out of this is that it has personality, it has soul. It wants to grab your attention. The delineation is remarkably good. Maybe 90% of what the big brother can do. One bad point for the r2r 11 mkii, there is a quite loud popping noise going from PCM 88khz to 44khz that the big brother does not have.
Ultimately, timbres are not as refined with the r2r11 but the expressivity of the midrange makes it still very enjoyable.
On Stan Getz Cool Velvet and Strings, the r2r 11 handles the tricky strings attacks without burning your eardrums. It will show the limitations or the recording with less mercy, indicating a more raw sound, closer to the actual recording. This is to be expected with NOS.
On Desmond/Mulligan Two of a Mind, the r2r 11 does very well. This is not a very dynamic record, and it is rather putting midrange under the spotlight instead. Mulligan's saxophone has excellent expressivity and rather convincing timbres. The r7he is ultimately more realistic, but not much more expressive.
On Getz/Gilberto Best of Two Worlds, the r2r 11 shows good rythm, and to be a charmer. Voices are rendered convincingly, but not quite as well as with the r7he mkii. Bass is well defined but lacks some lower extension in comparison. A better RCA cable could certainly help here. One element that stands out with the r2r 11 mkii is the excellent microdynamics. Such competence at this price point is remarkable. The midrange is excellent and bass performance is also impressive. The treble is not weak either: soft with very good accuracy. I am impressed. The result is more enjoyable i thought it would be.
With configuration #2
Things are significantly closer to what i would get with the r7he mkii. This is shocking!
Jitter has obviously gone down a big notch. Staging and bass are much improved. Not quite where the r7he is, but this really impressive. This gain in accuracy shows that the treble is not quite as velvety as before with harsher recording, which indicates better transparency (the r7he also has the advantage there). Attacks are sharper now, but still not as good as with the r7he either, while imaging and staging are close. This shows how detrimental jitter is to digital to analog conversion. Using the usb input, the r2r 11 gives somewhere around 90% of what the r7he mkii can do. Wed fed this high-quality SPDIF signal coming out of the di20he, it is closer to 95%. I imagine that using an i2s input (something Kingwa likely can offer eventually), the level of performance could be even better.
In both comparisons, i refer to the sound of the r7he mkii clocked by the Afterdark Eva in OS8 mode, fed through its i2s input by the di20he also taking its heartbeat from the Afterdark. The comparison is done from memory regarding the sound of the r7he mkii, as I can't switched between the two sources at will. Having logged thousands of hours of listening with the big DAC, I am confident about the accuracy of my observations.
From this comparison, i conclude that the digital source feeding the r2r 11 mkii has tremendous incidence on sound quality and even more so on sound signature, which becomes remarkably close to that of the r7he mkii. For me, this test shows that this new dac/headphone amplifier can perform at a very high level. I am shaking my head in disbelief as i am listening to the Getz/Gilberto album writing this paragraph. We are talking high-end sound here and some could even prefer the r2r 11 mkii because of how pure it sounds. Something to take note of: you have to buy 5000USD worth of equipment to achieve this result. One could consider a less expensive DI like the regular di20 and an affordable 10M reference clock and still get a substantial upgrade in my opinion.
It just hit me that when using the usb input, the signature of r2r 11 mkii is that of the Amanero interface. Not the latest version, which is synched with the main board's clocks on the more expensive Audio-gd dacs, but rather the sound of the former Amanero module with clocks on board, which the mkii still uses to keep costs low. This reminds of getting a similar upgrade with my 2019 r7he when inserting the di20he into the setup.
E. Conclusion
The r2r 11 is an excellent NOS dac for the money and a very competent headphone amplifier.
The qualities of the original r2r 11 (musicality, balance, spatiousness) are more evident now. What is more, the sound has gained in neutrality. This translates into putting the recording defects more in evidence, but also the strengths, in most cases. In addition, a gain in smoothness has been made, such that very little fatigue is induced, less than before in fact. The background is blacker, staging and imaging have also progressed considerably.
With the addition of features such as a display, a remote-control and new settings, the r2r 11 has improved in terms of versatility and usability. The first impression when acquiring this new unit is that the extra cost is more than justified.
But that's not all.
The r2r 11 mki has an ace its sleeve: it can sound like a very expensive dac when fed an exceptionally good SPDIF signal. Doing so, you are rewarded by the usual traits of very high-end sound. Still, the r2r 11 mkii will show its true distinctive colors: purity, musicality and balance. I am shocked by what it can do under ultimate conditions. It makes you realize that minimizing jitter is key. I think i will not get over this finding before some time.
Highly recommended!
*** UPDATE *** (01-05-2021):
I have to make an update to my review. The mkii required more than 340h. Now at 450h, it brings more to the table. The sound in the office setup is crisper with added resolution and size to staging. The bass got a bit deeper, clearer, imaging, more pinpoint. So as far as the recipe, it is yet more in line with the original. I felt that something was still missing, like there was sort of a veil. I was right. Listening to Gillespie Concert of the Century, the result is punchier, more lively and richer. At this point, i would call the sound as exceptional for the money. Like the original, it does not make your feel like you bought a device with sonic compromises. There are some, surely, but listening to it as i am writing, i hear none of them. I rather hear its brio in rendering captivating music. And again, great staging.
