FiiOK11 R2R DAC and Headphone Amplifier for Home Audio or PC, 6.35mm and Balanced 4.4mm, RCA, Coaxial, Optical, 1300mW, 384kHz/24Bit DSD256 (Silver)

First the bad. This is not the most user friendly. It can be confusing to cycle through the options. That definitely could use improvement but at this price point that is getting picky considering everything you’re getting here. Personally I could care less about the headphone amp, I’m using it strictly as a DAC with fixed output. Nice option to have though and I’ve read it does fine with hard to drive cans however I have not tried the amp part. I use the headphone jack of my Yamaha Aventage AVR currently but mostly listen to it through speakers both in straight stereo(Pure Direct or 2.1) and also the dts virtual mode which I hadn’t previously been impressed with but with this DAC with these room acoustics it works marvelously. My source is a WiiM mini with an optic cable capable of 24/192. I will eventually connect my Oppo 103 bdp via digital coax. I currently have this surround system set up as a 5.1 in my bedroom. I have this R2R DAC set on NOS, yet to try the over sampling. This is my first non delta-sigma DAC and I’m blown away at the sound quality of this DAC. I definitely prefer R2R(resister ladder DAC) to delta-sigma in general. I was surprised by the clarity, especially the highs. I thought they would roll off more, sacrifice some detail for smoothness yet more than enough is there that I didn’t feel like I was missing out on anything. It is smooth and more authentically analog-like which is what I like best about this style of DAC yet the highs are clear and present without being overdone of course. The mids are prominent, vocals and guitars etc sound real and natural, not subdued, not overwhelming. They can be more forward and prominent on some tracks depending on how they're mixed. The bass is thick and quite full yet not overpowering the mids and highs. Bass is not especially tight yet very pleasing. Maybe it’s just the honeymoon stage but so far this is the sound I was hoping for. I’m thrilled to have a DAC this good for so cheap. Both acoustic and electric instruments play beautifully through this DAC. For the curious I’m not an audio expert. I am an audiophile on a budget. I don’t care about measurements and other technical jargon. I care about usability and sound quality, build quality and price, then looks and size. Build quality is good here, not spectacular. I think it’s good looking. I like the rubber pad underneath but as others have mentioned due to its size and light weight you still must hold it well to attach/remove cables. No biggie for me, to be expected.Obviously your results will depend on your gear and taste. While I’m not claiming to be an expert I do have a clue. I’m a mid-50s music addict from the rock and roll capitol of the world(though other cities may refute this). Been into sound quality since I was old enough to comprehend music and tv. Always tinkering trying to improve sound since I was a kid. I listen to mostly rock and blues, reggae, metal, folk, a little country, some jazz and classical on rare occasion. I own an expansive collection of DVD-Audios, SACD, Blu~ray music, concert DVDs, vinyl, some HDCDs and of course regular CDs. I stream Amazon Unlimited HD from WiiM minis and a Pro, plus my phones and tablets via camera adapter to DAC. I also use a Schiit Modi 3 with Monolith Liquid Spark headphone amp(my Liquid Spark DAC that I loved died), a Monolith Liquid Platinum DAC with its companion Monolith Liquid Platinum headphone amp(duel tube hybrid), and a Geshelli JS2 with Sparkos op-amp(SE) to my late model Sony ES AVR(7.2.2 set-up) and the Alex Cavelli Drop tube hybrid headphone amp(the Sony has no headphone jack). I love all my gear and I use them in different ways in a couple different rooms. For the moment my FIIO K11 R2R DAC is my pound for pound favorite. Too new to know about longevity yet no issues so far other than learning how to operate it. Edit: one issue although I’m not sure if it’s source. On several occasions the music has stopped. I’m not sure if it’s the DAC or my streamer but I don’t recall this issue when I had the streamer wired directly into the Yamaha(via optic). It starts up again after several seconds to a minute or so. Could be internet too but I’m close to the router and I get upper 400s MBPS.Also for the curious my gear for this set-up is Yamaha RX-A730 AVR, WiiM Mini, Oppo 103, Andrew Jones designed Pioneer towers, center, bookshelves and sub. I just received another K11, this time in black, that I’ll swap out my Schiit Modi 3 to my Monolith Liquid Spark headphone amp to try it with my cans. I own the Sennheiser Drop 6XX, Sennheiser 599, Beyerdynamic dt990, HiFiMan 400i, Phillips Fidelio F3, Monolith M1570, Monolith M650, Status Audio OB1 & CB1, and a few others. Eventually I’ll get around to trying the headphone amp part just out of curiosity, not expecting too much.Update: I’ve since purchased a WiiM ultra for my main set up and linked the K11 R2R to my WiiM Pro with an info Silent power supply in my bedroom via digital coax. Sounds better than ever. Having 2 of these FiiO K11 R2R DACs I tried the headphone amp part. Was not impressed. It was ok and was able to drive my cans but it lost the magic I hear using it strictly as a DAC. Whether listening to speakers or through the headphone jack on my 2013 Yamaha Aventage AVR blew the K11’s amp away. I also compared it with my Monolith Liquid Spark amp and the Spark was way better and with more oomph. The K11 wasn’t lousy just no wow factor. Also of note I think my Schiit Modi 3 actually pairs slightly better with the Spark than the K11. It may be that the Spark is a warm amp and benefits from a DAC not quite as smooth as the K11. Or perhaps it was just my mood that day. The K11 wins handedly paired to my Yamaha.No matter what I love this DAC and for my taste I rank it the best in the $200 range(Schiit Modi best under $150). Now I wonder how a legit high end R2R would sound although m well aware of the law of the diminishing returns. No way a $2000 DAC will sound 10x better. I am curious how this stacks up to the Schiit Modi Multibit($300) and Bifrost($800) which are more or less R2R hybrid DACs. I’ve not heard either.

First things first, good luck trying to find another R2R DAC for under $400, much less $200. I feel like they could've charged the same for a standalone DAC and no one would blink an eye.With that out of the way, let's go straight into how they sound. Within seconds, I knew they were tilted warm. If you're looking for something dead accurate or analytical, this isn't for you. Plain and simple. However, if you don't do any audio mixing, or are using this solely for listening enjoyment, read on.For the moment, I'm using the 4.4 balanced output into either a Sennheiser HD6xx or Hifiman HE5xx. I'll start with the HD6xx since I think it's become a common benchmark in the scene. The warmness is either hit or miss in terms if it sounds better than purely neutral. While not completely consistent, I did notice that some male vocals would sometimes almost sound veiled or muddy. But it's strange because I can definitely hear everything resolving, so I wonder if my ears just needs to get used to the warmness. On tracks where the highs and female vocals are a little too spicy, I did notice that the R2R gave it a much smoother rolloff, basically turning sharp frequency spikes into curves. The HE5xx has it's own character independent of whatever DAC you use, for better or worse. It seems like the R2R keeps all the good and fixes all of the bad. Highs are more reined in, mids are pushed a little more forward, but all the of lows are still preserved.In both cases, I think there was a overall improvement to music enjoyment. Since the sound isn't analytical, I don't find myself straining to listen to details. I instead find myself being able to sit in the music and much less fatigued after longer listening sessions.Power-wise, I'm barely able to get to 40% at high gain on both cans. At 50%, I can put my headphones on my desk and use them as monitors (with no distortion). There's comfort knowing that I could easily drive harder to run headphones with this kind of headroom.Build quality is excellent. The metal has a good weight to it and gives a nice outer finish to the unit. The volume knob is quite nice with some nice knurling. LCD and RGB are plenty bright and adjustable. One thing that surprised me was the size. I don't know why but I was thinking it would be closer to the size of a Mac mini, when in reality I would say its closer to half the size. Only thing that's slightly annoying is that like a lot of recent audio gear, it's a single knob for every function. Volume control, navigating menus, choosing sources, and selecting gain level is all done through that same knob. I would've at least liked at least a dedicated gain switch, but this is a minor gripe since I only change gain if I switch between my IEMs and my headphones, but I tend not to do that too often after I do my initial testing.As mentioned before, the main downside to this unit is that I would not recommend this for anyone who does professional audio mixing or editing in any capacity, especially in NOS (non oversampled) mode. This simply has too much color for that purpose. You can somewhat mitigate this by turning on OS as it'll go a little cooler and more analytical. However, at that point I think you'd be better off with the non-R2R K11 and just save the $30.