Singxer SDA-2c



The Singxer SDA-2c was provided to me by KitsuneHi-Fi and is a demo unit, this unit is not my own and I was not asked to do anything but provide my perspective on it, as I have a couple of AIOs in my possession of varying degrees of “value” and pricing, which to compare against.

KitsuneHi-Fi is the only place to get HoloAudio gear in the US(outside the used market) and is worth checking out, as I find the Black and Copper aesthetic rather fetching, and the HoloAudio gear I have heard sounds pretty damn good (Cyan DAC/amp). The Singxer unit is not a part of the HoloAudio line just to be clear.

The SDA-2c is a balanced DAC/amp all in one (AIO) unit with pre-amp capabilities (I used it with my JBL 305s). It runs the XMOS xCORE-200 series chip for USB audio, the AKM4497 DAC, the AKM4118 digital audio input receiver chip, and the STM32 to control everything, Xilinx large-scale FPGA processing the clock system and digital audio stream…Ok, there is a whole lot more of this… this thing has a lot of tech built into it, all to give it a great no jitter, best possible sound output by using quality parts implemented a specific way… this is all “Greek” to me, so if you are more into diving into the tech please feel free to contact KitsuneHi-Fi at the above link and reach out to them, they are very happy to talk to you more about it, and the other gear on the site.

Needless to say, this thing is jam-packed with technology…so onto the Specs.

Specifications as per product page:

So I was going to list it all out but seriously there is a ton of tech talk and specs so I’m going to pull a wall of small print move here and just copy-paste it all in very small print to save some room, you can also just check out the hyperlinks above to take you to the product page where it is all listed and skip to the next section. Plus, if you go to the web page, they have some measurements, for those so inclined to gander at such things.

" 1. USB part uses our first generation isolation technology: SCIT technology (Singxer capacitor isolation technique), SCIT technology is a full isolation technology (ground isolation), high-speed signal using 150Mbps isolation chip, low-speed signal using optocoupler isolation It can completely isolate the interference from the PC; the USB version of the high version can basically reach the level of the SU-1 independent digital interface.

2. source synchronization technology and FPGA shaping technology, re-shaping the isolated I2S signal; thus eliminating the additive jitter caused by the isolation chip;

3. The self-developed clock system uses a femtosecond crystal oscillator as the local reference clock;
, 4 way class A discrete amp circuit, full balanced amplification of 8 patch transistors per route.
Technical indicators:
Sample rate supported by each input interface:
PCM: 44.1KHz, 48KHz, 88.2KHz, 96KHz,
176.4KHz, 192KHz, 352.8KHz, 384KHz
[Which USB and I2S support all sampling rates, S/PDIF supports up to 192KHz]
DSD: 2.8 MHz (DSD64) – DoP, native
5.6 MHz (DSD128) – DoP, native
11.2 MHz (DSD256) – DoP, native
22.5792 MHz (DSD512) – native
[USB and I2S support all DSD formats, S/PDIF and AES/EBU support DSD64 DOP mode]
Bit width: up to 32 bit over I2S output
Up to 24 bit over S/PDIF
Electrical standard of each interface:

1. USB input socket is standard USB-B type female socket, USB power supply range is 4.5V-5.1V;
2. SPDIF interface inputs standard S/PDIF signal, input impedance is 75 ohm, AES input impedance It is 10 ohms;
3, the power input is 115V/230V AC, and the internal 30W O-type transformer is used for power supply;
4. The I2S input is LVDS level in the form of HDMI interface, compatible with SU-1 interface;
Analog Output Performance:
Output Level (0dBFS):
PCM: RCA single-ended output is 2V RMS, XLR balanced output is 4V RMS
DSD: RCA single-ended output is 1.8V RMS, XLR balanced output is 3.6V RMS
Output impedance(backside): 22 ohms (RCA single-ended) / 44 ohm (XLR balanced)
(XLR 4pin BAL) headphone impedance is less than 2Ohm
(SE 1/4) headphone impedance is less than 1Ohm
Frequency response: 20-20kHz +/-0.2dB
Signal to noise ratio: 125dB
Distortion characteristics:
THD+N (1kHz, 0dBFS) 0.0002% at fs=44.1Khz(PCM)
THD +N (1kHz, 0dBFS) 0.00023% at DSD256
dynamic response (1kHz, -60dBFS) 125dB
channel separation >125dB
Balanced output noise floor: 2.2uv RMS
Amp balance maximum output power 3480mW@30Ω, 0dBFS
Load power
30Ω 3480mW
75Ω 1640mW
150Ω 920mW
300Ω 440mW
600Ω 220mW
Distortion of the amp balanced output, 0DBFS, fs=44.1Khz (PCM)
75Ω load THD+N -110dB
600Ω load THD+N -111dB
"~ KitsuneHi-Fi Singxer SDA-2c product page

Seriously this has a lot of cool stuff going on… but I am just here for how it sounds.

Review kit and tackle

As this is an AIO review, I did more of a comparison vs. on hand AIOs. Monolith THX-788, Audio-gd 11.28, and the current king of AIO the RME ADI-2DAC (don’t take that too seriously, just seems like this is the current AIO/DAC to beat right now). Transducers used, ZMF Verite, ZMF Aeolus, Focal Clear, Sennheiser HD800(SDR mod). Music used is a combo of FLAC files, Qubuz Studio lossless streaming and lossy Spotify premium. I have a Spotify playlist that can give you an idea of some of the tracks used, as I try to keep the same tracks across the two streaming services: Music for Forum.Headphones

Options on this loaner

This model is the SDA-2c which has upgraded components specifically Crystek Clocks. The advanced version essentially has more tech around the USB input to help with jitter etc. and is recommended for those using USB input.

Build what is/was included in the box

The Singxer SDA-2c, a power cord, and a pretty nice USB cable. Ok, that is it, move along…

Output modes/pre-amp

Pre-amp works rather well. It is nice that you can switch between headphones and speakers and control both outputs volume from the SDA-2c. You just have to hold down the PRE-OUT button down until it switches, just be careful as if you leave it on fixed your speakers will blast at whatever volume you have them set to. Also like a lot of AIOs that work with speakers, you can’t swap outputs, they both play at the same time. On my particular setup, the JBL 305s sounded good and I didn’t have any issue with them being played through the SDA-2c. I will say it was not my preferred method, it didn’t sound as “clean” as I’m used to with my standard of using the JDS El DAC with the JBLs.


Single-ended and Balanced for headphones. In the small print up above, it goes into the power outputs for all of these, and I don’t want to steal that thunder… so basically this covers all desktop needs as an AIO. It does XLR out to powered monitors, SE and balanced outs for headphones. I used almost exclusively balanced out for my headphone use while using this. But during comparisons, I would use SE if the other AIO didn’t have balanced as an option.


(Caveat I will be “exaggerating” what I’m hearing, the differences are fairly slim but noticeable. For music I’m bouncing around on my Qobuz favorites tracks.)

Ok time for the meat and potatoes, this thing sounds really good. Ok done… review over…oh…you want more…hmm…ok…let me think. (caveat, I’m still pretty new to reviewing DAC performance, so take the below with that in consideration, as I’m still learning how to pick apart what I’m hearing).

Seriously though it sounds really good, I enjoy how it almost has a “tube” sound to it. It really showcases the AKM Velvet sound….in fact, it oozes it!

You can swap between a couple of different digital filters as well to fine-tune your preference: NOS/LOW/SHARP/SLOW/S-Sharp/S-SLOW. I tend to leave it on SHARP, but your mileage may vary…it is only a button press away to see what you prefer. But to note these differences are very minimal and unless really listening for them are almost non-perceivable to most unless you know what you are listening for.

Imaging is pretty spot on with the SDA-2c but feels closer together without being claustrophobic. I love how it separates the different instruments and places them, but not too far apart to become overly analytical, for me it seems to have a nice placement.

Staging is decent, it has a slightly more intimate feel to it. I don’t get super wide or narrow staging more middle of the road.

Bass can be a little bloomy depending on the track, and headphones, while Highs give a nice sparkle but with a more relaxed feel to them. They can get lost in overly bass-heavy tracks, but not because you can’t hear them, just the bass comes through “heavier”. Mids are actually very forward and vocals shine really well on this AIO. If you like either bass-heavy, tracks or vocal music you will really like this AIO. Now, this doesn’t detract from the highs as they are still there and sound great, they just get pushed back a bit by the Mids and Highs.

Tonal balance, well honestly not much to say here, it felt “right” to my ears…I didn’t pick up any issues, so not much else to say really.

This is at least in my experience with it while listening with the ZMF Verite especially. With the ZMF Aeolus the Mids become way more focused, bass tames down a bit…image/detail retrieval suffers a little bit. Treble is still pushed back with the Aeolus and has a similar profile.

With the Sennheiser HD800(SDR) Mids are even more pronounced, the stage goes very wide, the bass gets tamed way down, and Highs begin to shine through. But Mids are still the leaders of the pack. Detail retrieval and imaging is not as good as the ZMF Verite but it is pretty close. Overall a “brighter” experience to the ZMFs.

Focal Clear is probably the most subdued/neutral of the bunch. It flattens it all out, Mids still seem to be forward but, not as much, as with the other headphones. Feels like some of the detail is lost compared to the others though, which I wasn’t expecting.

Overall depending on the headphones, you have, this is an enjoyable listen. Plenty of power, and gives musical performances that are engaging but in a more enjoyment/relaxed way, while still providing excellent imaging and separation. The words intimate/natural/relaxed come to mind while listening to the Singxer SDA-2c. This is definitely colored by what headphones I’m using, so please keep that in mind. Also, this is no slouch at detail retrieval either, I rather enjoy listening to this AIO.


I didn’t really use this feature, but if one was so inclined, based off my experience with the PCM side of the house I can’t imagine people finding any major faults with the implementation.


Volume control is nice but not analog, stepped digital, not as many features as other AIOs, such as EQ options…but you can just as easily do that via software on your computer. It gets rather warm above the volume pot…not warm enough to worry about or even be bothered by, but it is there.

All In One (AIO) comparisons:

Caveat I will be “exaggerating” what I’m hearing, the differences are fairly slim but noticeable and during longer listening sessions can cause fatigue/or, not depending. For music, I’m bouncing around on my Qobuz favorites tracks.

Vs. Monolith THX-788 (used ZMF Aeolus)

Well, I think these two are approaching AIO from different perspectives. The THX feels wider and cleaner. Separation feels slightly better. More fatiguing treble, and overall not as enjoyable as the Singxer. It feels more “harsh” to me. That being said the THX-788 is still my recommendation for AIO or even DAC/amp under $600, and honestly even higher depending on your preference. The THX-788 is a more analytical sound and it has EQ options (a little hard to figure out at first but once you do it is pretty easy to get around the menu). If you are looking for the best bang for your buck, I would go with the THX-788. If you want a more relaxing involving sound and don’t mind not having EQ options baked in and don’t mind the price, or will be potentially pairing with better amps down the road, Singxer SDA-2 is the option I would go with.

Vs. Audio-gd 11.28 (Used Focal Clear)

The 11.28 has a more subdued sound, or, hmm…something is off with it. It seems messy, lots of bleed over. The imaging is ok and the stage is decent…but man it is messy and kind of a cluster. This is not an easy listen. Ok, let’s try a less busy track. Hmm…much better. That might have been a bogie track…but even still…I can’t listen to this for long…my ears have become refined lol…this is too “punk-rock garage band” for me.

The 11.28 is still not great, and it doesn’t come close to the other 3 on this list…but for an intro AIO, probably anything $200 and under I think it is a decent grab. But I would probably recommend the JDS Atom/Schiit Modi combo over this at that price. It has plenty of power though, so maybe if you bypass the DAC and go for just the amp? But once again there are better amps for the price…

It isn’t even worth the time comparing to the SDA-2…it doesn’t even come close.

Vs. RME ADI-2DAC (Focal Clear)

Damn, I really like this AIO (the RME ADI-2DAC) it not only looks amazing but sounds fantastic with features and tech out the woo-ha! Separation/imaging/stage/highs/mids/lows… all just blend and whirl around in an almost perfect symmetry…Now I’m very biased by this and it just fits my ears, so take that for what it is.

Now the Singxer SDA-2c is no slouch here though, and I’ve come away impressed by it. If it had the EQ feature alone, I would take it over the RME ADI-2DAC…heck if it had the display, I would be hard-pressed to not pick it over the ADI-2DAC. It is kind of how I feel about my ZMF headphones, it just adds that Lil bit of “musicality” to the mix and moves ever so away from the analytical, while still having it if you want to analyze what you are listening to.

I wasn’t really expecting it to compete so favorably with the ADI-2DAC as an AIO, but I think that if you were specifically going for an AIO and didn’t want/need/desire to upgrade amps down the road… I have to say the Singxer SDA-2c is the way to go. It just sounds damn good. I think I can leave it at that, ha, but I guess due diligence and what not…

The ADI-2DAC really shines in its performance as a DAC, not an AIO. Though it is a fantastic AIO, and I can’t imagine anyone being upset with it, especially knowing down the road if you wanted more amps to pair you have one of the best DACs on the market to do the 10010100101011 work.

Now, the SDA-2c also can be used as just a DAC and is a pretty damn good one, so the same down the road amp statement still applies here as the ADI-2DAC, just without all the features. But it is still a great sounding implementation of the AKM AK4493EQ.



So here we are, you stuck through the small print, the meandering writing, and you have to ask yourself…is it worth it?

Well, I think it is, even with the limitations of not having EQ. I think it fits nicely in the price bracket it is in, I definitely think it sits above the THX-788, and below the ADI-2DAC (this thing is hard to beat pound for pound though, RME really broke the standard here).

The SDA-2c just sounds good, plain and simple. It is engaging, with just the right amount of clarity, and tonal balance to either pick apart or sit back and relax with your music. I do think it pairs slightly better with a more neutral headphone, such as the Focal Clears, HD800, and the ZMF Aeolus. With the Verite, it on occasion would get a little too bloated in the low end, but not too horrible, but having the others cans on hand, and knowing that I can reach for one of the others first, doesn’t make it a big deal for me.

As I sit here listening, I can easily recommend this as an office setup, or college, limited desk space AIO. It is simple, and sounds good and if you prefer to just turn on a thing, plugin and be ready to relax, without having to worry about EQ, or turning on other amps, etc. Or are just looking for a simple turn on and go solution, this very well could be the one to beat, in that realm. But it does have some stiff competition in the THX-788, I mean it is not an insignificant amount cheaper than the SDA-2c, and plenty of people will be completely content with it. Yes, there is another “but” coming, but, if you are looking for that next step up, with a more resolving, enjoyable listen(at least for me) I wouldn’t fault anyone for going for the SDA-2c, it really is a great sounding AIO, at least to my ears.


Excellent review. Very detailed and easy to read. I enjoyed reading it as I always do your reviews.

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Great review!

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Thank you gentleman!

Nice review!

Almost makes me want to break my self-imposed “new gear moratorium”. Though I’d just be doing it to see if someone had finally come up with a worthwhile AKM4497-based DAC that doesn’t cost a couple of thousand dollars.

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Very nice review. Do you have list price and if applicable a typical discount price? Or is it one of those units/companies that never permit discount?

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I think they are currently on sale over at Kitsunehifi…here is the link:

I think it goes for just shy of $700? If you reach out to Tim via the contact page and ask if he has any discounts for it he might throw one your way? My philosophy on that kind of thing is “the answer is always no until you ask” :wink:

More curiosity than need. Wanted to place it in the cost spectrum. Now if you happen to have wheel trim strips for a 1964 Olds F-85, I’d be jumpin’ on those like gravy on potatoes.

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Nah, those are easy. Wheel well trim (chrome) and lower side aluminum trim strip ( below doors). The aluminum rots, and decent condition wheel well trim is almost unobtainium.

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