Galvanically isolated his brain
Pros: AK4497 + XMOS + OPA1688 with Yulong's expertise
Cons: built-in headamp is a gimmick
Hi guys, recently had the opportunity to borrow this shiny box from my local reseller and figured a review would be in good order as Yulong don't appear to get the coverage they would deserve: http://www.yulongaudio.com/pd.jsp?id=39#_pp=106_674
It's got all the bells and whistles you could think of:

-latest AK4497 DAC chip

-Native DSD64/128/256 + PCM 16-32bit, 32-384 KHz via XMOS-based USB
-DOP64 + DOP128 through S/PDIF, Optical and AES
-PCM 24bit 384KHz through S/PDIF, Optical and AES

-Fully balanced decoder topology + fully balanced high current preamplifier
-Fully balanced headphone amplifier
-OPA1611 with ultralow distortion for LPF + high current OPA1688 for output buffer
-99 steps volume control to the headamp or preamp
-Universal mains power with a switch for 110V or 220V operation

I'd rather save you from a TLDR review so here are my thoughts after playing with it for a week in no particular order:

-Specs are very similar to DA9 minus the discrete headamp as it's now TPA6120 based, but still balanced
-OPA1688 is a high current opamp that I really enjoy in other equipment
-AK4497 is the newest & highest grade DAC chip from AKM: https://www.akm.com/akm/en/aboutus/news/20160107AK4497_001/

Real pics:

And these are the "unique claw-style suspension feet":


USB drivers are not provided in the box and must be downloaded from http://www.yulongaudio.com/col.jsp?id=111

I knew about Project86's review of DA9 but preferred reading it afterwards and I would very much echo his impressions that "filter type"(Sharp, Slow or Super-Slow roll-off) and "sound mode"(1-2-3) make hardly any audible difference at all. I got them set to Sharp & 1 after quite a lot of A/B but I wouldn't bet being able to DBT them:


Project86 didn't appear overly impressed by DA9's discrete headamp and Aquila doesn't have it in order to drop the price of the unit as it's been replaced by a dual TPA6120 with 4.7Ω output impedance. I solely own low-impedance headphones so it appeared quite colored to my ears, but then again I have personally lost faith in built-in headphone outputs of DAC units and it makes more sense to me to use a separate headamp that can be finetuned to your taste, so as you can see on that picture I got it set to "Pure DAC" mode with headamp/preamp disabled.

Another non-TLDR review of Aquila was posted a few months ago: http://www.soundbsessive.com/yulong-daart-aquila/ and here a few quotes:
Tonally wise, the DAC is very similar to the DA9
Aquila outputs wide soundstage and imaging that’s both clear and not hyper sharp. Instruments and effects are precisely located, almost visible, but without seeming etched inside the room, which would have otherwise sounded unnatural (this is something that happens with some ESS Sabre chips).
Aquila is a DAC that’s “tonally transparent”: it’s neutral, never calls for attention, but it’s still very detailed and doesn’t over represent any frequency. It has tons of inputs and can read pretty much every format. It’s a very high quality DAC and Pre-amplifier combo, with a very clean signal

So there we have it, it sounds very clear without the usual Sabre shrillness that kinda got me off the D/S DAC train and because it runs a whole lot of excellent chips such as AK4497 + OPA1611 + OPA1688 + XMOS together with Yulong's expertise it really makes for a great DAC in order to feed an amplifier via RCA or XLR.

As I see it, the whole point of Aquila is to essentially provide a DA9 without the discrete headamp for cheaper and I see it selling for less than $800 so if you can combo with a sale it really makes for a worthwhile AK4497-based source + digital preamp to my ears :)