a short diary of some part of my life.

Posts tagged NuForce

Office Headphone Setup

CEntrance is one of the few companies who offers driverless USB audio. They are not some companies who commission someone to make a product for them and label it as their own or a company who sells mostly overly hyped products that do not perform anywhere close to the high price tag, typically found on boutique brands. They are a design-engineering-driven company.


A lot of geekery trends were made mainstream by geeks and nerds. Geeks tend to be curious at new techs. Some of the techs are not necessarily ready for consumers but they still buy them. Thankfully, early adopters are now becoming public-beta-testers for those techs. A lot of bugs will be fixed, revised or even redesigned by the time the tech reaches mass-market.

In the early days of USB DAC, everybody did not seem to mind installing, maintaining, and updating drivers. Now, we want driverless solution. USB DAC solutions have matured to the point where we no longer have to tinker to use them. It’s now plug and play (on Macs).


Ever since I saw DACport for the first time, shortly after it is announced, I immediately felt this is the gear that I should try (partly because CEntrance is the maker). Normally, I don’t buy the first runs, I want to buy a gear that has been publicly tested. So, I purchased it. Long story short, it performs like a champ since day one. It’s been what? 3 years since its introduction and I hardly found anyone having problem with it.

Design Philosophy

Unlike many audio gear makers, CEntrance tries to keep much of the heavy-lifting to the gears they are making. Things like clean power, the need of isolated ground, ’boutique cables’, superb S/PDIF signal are not issues users must provide. They are actually helping us not worrying about those things and let us enjoy what really matters, which is good music, really. They are also not some random companies (some of them are quite famous) who sell half-baked gears.

As NwAvGuy wrote:
I completely agree some products are hastily thrown together using trendy components, made to look high-end, and rushed to market in search of quick profits. Other companies, like Centrance, take a much more holistic approach and put genuine high-end performance ahead of aesthetics and time-to-market. The quality of such products is more than skin deep and they pay a lot more attention to getting the normally hidden details correct.

Sound Quality

As what I have written about NuForce uDAC-2, the DACport is the better product. But not by a wide margin. It’s definitely better in every area. Compared to the uDAC-2, I can immediately hear a sense of speed, space, precision, and airiness. You don’t feel constrained with little guy. I’m accustomed to great bass slams (quality, not quantity), DACport will give you that.

It’s a refinement of what the uDAC-2 should have been. I think it’s either Nuforce got lucky or improvements in audio is really that small. Either way, this is the benchmark of a USB powered USB-DAC. This will be a classic or it already is.

Compared to a desktop amp, say a Schiit Lyr (w/ stock tubes), DACport excels in a few areas like speed and airiness. When I’m out of the house, without my desktop amp, I don’t feel I need of anything more than the DACport. It doesn’t make me miss my Lyr. I’m perfectly fine without the Schiit amp. It is that good. And when I use it as a DAC, it performs even better. A friend of mine who also owns a DACport run it as a DAC for his speaker setup claimed that he couldn’t differentiate his desktop DAC and his DACport. Too good? Maybe. But I have heard quite a few people whose experiences match my friend’s findings.

For IEM, the gain is too high for my taste. I like to listen in low volume range and it barely allows me to do that. Fortunately, unlike many portable DAC/amp, this one does not suffer from channel imbalance. There is zero detectable hiss at high volume range. I would like to have a bit more wiggle room to fine tune the volume for IEM. That’s the only con that I can think of.

For full size headphone, like my Grado RS1i, it’s a great match. Grado is notoriously known for its ‘smallish’ soundstage. Well, DACport fixes that. It doesn’t sound like many artificial soundstage inferior amps produce. Its sound placement and precision are just right where I want them to be. All the great traits about Grado house sound are retained and refined. Bass is deep and articulate. Micro-details are presented in a manner that does not pierce my ears.

I think this is the best portable DAC/amp in the market.

Build Quality

I consider my HeadAmp Pico to be the best in class in term of build quality in portable amp/dac world. That remains true with the intro of DACport. There are slight misalignments here and there on the DACport but nothing worries me. The finish is also better on the Pico. But Pico is the best, to be fair without a comparison with Pico, DACport is still miles better than the rest of the competitors. Have you ever seen any iBasso amps? If you haven’t seen one, if DACport gets 10-point, iBasso gets 6-point. Don’t even think about looking inside, iBasso gets an even lower score. Pico and DACport are engineering marvel. Look now, my uDAC-2 is already dead and it’s only been 3 years. I expect DACport to last for a long time, maybe not as long as my home gears due to the stress it often gets from frequent travels.

The Highest Recommendation

This is it, look no further. You don’t need to follow the trend. New products will keep coming but DACport will still be one of the best. There are not many companies out there who have the resource and expertise to compete directly with CEntrance. This is purely them outmuscling the competitors. They set a benchmark of what a portable amp/DAC should be.


I have never really looked at NuForce offerings until the new uDAC-2 came out recently. I tried the first generation uDAC, while the sound quality is good for the money, I dislike the channel imbalance it produces on low listening volumes. The sound of the first gen uDAC is also too warm and soft for my taste.

The new uDAC-2 is a step up over the first uDAC (uDAC-1). NuForce listened to customers complaints and suggestions about the uDAC-1. They tweaked some of weaknesses found in uDAC-1. The results are quite good. Now, I have a proper headphone amp that I can use on the go, I can also use it as a USB to S/PDIF converter. I no longer own any high impedance full sized headphones as I find them not good enough at times. So the uDAC-2 is only used for IEMs and efficient headphones that do not require huge power output to drive them properly. I don’t own the most neutral IEMs or headphones, my impressions are based on my listening sessions with my Sennheiser IE8 and Grado RS1i. Those two earphones and headphones should match or exceed some of the best full sized headphones out there. There are compact enough which is good for my hunger for simplicity at home.

ESS Sabre

Let’s start with the chips used in uDAC-2. It uses ESS Sabre 9022 DAC chip. ESS Sabre DAC is one of the well known sigma-delta DAC makers. I own a Wyred 4 Sound DAC-2 which uses ESS Sabre 9018, a similar chip equipped with excellent implementation and output stages. The point is, I am satisfied with ESS Sabre as far as potential sound quality it can produce. Other than the DAC chip that is revealed by Jason Lim of NuForce, there is no other information about other chips inside the uDAC-2. If Jason did not reveal the chip, I would have not known the chip because it has NuForce markings on it instead of ESS’ markings. Before I started using the uDAC-2, I am disappointed to read that it does not support 24/88.2. I have quite a few recordings in 24/88.2, they are also my favorites. I bet it uses Tenor TE7022 as its USB receiver, the Tenor chip does not support 24/88.2.

I have a CEntrance DACport for comparison. The uDAC-2 was compared side by side, powered with the same USB ports on my MacBook Pro i7 2.66Ghz 8GB-RAM 500GB-HDD. I also compared it with my beloved R-2R DAC, Audio-gd Reference 5 DSP. I wanted to know how far this little guy can go. Oh and, about the build quality, the uDAC-2 seems very solid. My unit has a slight misalignment on the headphone jack, but that does not bother me one bit since it does not stress the PCB. Considering the low price, I can’t complain much about the chassis, it’s definitely solid. But if you compare it with some of the best audio chassis out there, it looks okay, I guess…

Design Philosophy

Before we get into the sound. I would like to mention a few interesting findings about the uDAC-2. I have several ‘toys’ that I can compare with, they are not necessarily made by the same company, in fact, they are all made by different companies. Why? To diversify and differentiate. NuForce is one funny company. They don’t measure their gears at all. Audio experts have been asking about this very issue. That’s not the only issue, the uDAC-2 is extremely sensitive to the USB power you are feeding it with. It needs to be extremely clean: free from noises, unstable power, ground loop. It needs to be isolated. CEntrance DACport on the other hand, is virtually immune to dirty USB power. It has multiple filters in that tiny chassis. It’s also isolating itself from outside interference. I think this is an interesting finding. CEntrance cares about what we should be experiencing, high end audio without the ‘necessary’ complexities. While with NuForce, this seems to be an afterthought.

As a headphone amp…

Vs. CEntrance DACport

CEntrance DACport (DACport) and NuForce uDAC-2 (uDAC-2) do not produce any hiss at normal listening levels. They are virtually hiss-free. One of the main reason why I want an external headphone amp in the first place is to get a hiss-free experience listening to my favorite musics and movies. I hate hiss. If you have OCD, DACport is quieter than uDAC-2, but the difference is not very noticeable, especially with music playing. The DACport has much more driving power, it has the juice to drive full sized headphones with ease. The uDAC-2 drives the IE8 & Grado RS1i with ease. It does drive the RS1i well but it lacks the juice to extract its full potential. I suspect, it will have problems driving more-difficult-to-drive headphones. I don’t have any plans to acquire one, uDAC-2 will do just fine with my current phones. DACport produces more expansive soundstage. Complex passages do not get lost with DACport. uDAC-2 falters at producing preciseness in complex passages. uDAC-2 is probably better for slower musics while the DACport is good for about everything. I was torn on which one to keep, I don’t want to keep both, technology keeps improving, so there is no need to keep both of them. There will be better products in the future and they are likely to be cheaper than they are now. I ended up keeping them both. It’s kind of fun finding out how a very well designed product (in this case, DACport) offers the refinements that the inferior product (uDAC-2) fails to produce.

As a USB to S/PDIF converter…

Now, this part is a lot easier to write. As usual, I used my Audio-gd Reference 5 DSP for this test as the DAC, my superb monitors, Selah Audio RC3R powered by Wyred 4 Sound STI-500 integrated amplifier.

Vs. Halide Design Bridge

Halide Design Bridge is a dedicated USB to S/PDIF converter, just like the Stello U2 from April Music. I posted a short impression of the Halide Design Bridge on my Audio-gd RE5 review. If you are too lazy to read it, the Bridge is the best USB-SPDIF converter that I have tried.
The uDAC-2 is noticeably warmer and less dynamics. The details are masked with inferior tonal balance. The sound placement is also affected, it’s not like attending live music. 😦 To sum up, there is no area that the Halide Design Bridge cannot beat the uDAC-2. Does it make the uDAC-2 sound bad? No. I don’t usually like non-neutral gears but in this case, I’ll make an exception. If you need a USB-SPDIF converter that can tone down your overly bright gears or if you prefer warmer tones in general, this is it. I’m not trying to salvage the uDAC-2 but not everyone owns the exact same gears as I own. 😉

As a standalone DAC…

NuForce uDAC-2 has a set of analog RCA output, I thought it would be good idea to give it a run, how it performs… The output level can be adjusted by using the volume knob on the face plate. Since the output level is adjustable, it can also act as a preamp. I didn’t test the uDAC-2 preamp capability as I no longer own a power amp. This product is very flexible and offers a wide range of usage possibilities.

Vs. CEntrance DACport

DACport and uDAC-2 were feeding the superb Wyred 4 Sound STI-500 integrated amplifier. The difference between them was more difficult to find than I first thought. I even think the difference was too subtle to be noticed. I ended up playing quite a few recording that push DACs to the limit and the result was just as difficult to find out. The uDAC-2 is just a bit warmer than the DACport and DACport background is a tad blacker. The soundstage, level of details, sound placements, etc… you name it, they are all very similar. I guess uDAC-2 performs better as a standalone DAC (using its RCA outputs) than a headphone amp.

Vs. Audio-gd Reference 5 DSP (Burr Brown PCM1704U-K)

Portables will never beat full size gears, this remains true with uDAC-2 Vs. RE5. The difference is not subtle at all. Everything is much more refined on the RE5. This is not a fair comparison. RE5 has overkill designs that can only be found in exotic gears while the uDAC-2 is meant to be small as it is. Let’s start from the noise floor, the uDAC-2 has higher noise floor while the RE5 has noticeably much lower noise floor. The soundstage difference is even bigger, the RE5 is able to bring you live music experience while the uDAC-2 which is still better than not having a DAC at all, cannot bring live music experience. Tonal balance on the RE5 is also far superior. There is this magical thing going on in the PCM1704U-K that makes the music flows without hesitation. The uDAC-2 is clearly inferior and it cannot keep up with full size gears, at least if compared with my RE5, it cannot keep up. For the size and money, I don’t think I can find a better product than the uDAC-2. And that’s exactly the point of why I should keep the uDAC-2 around. It’s small, it’s cheap, and it performs admirably.

Before one makes any purchasing decisions, please do compare them side by side if possible. Go to a local meet and makes friends there. There is no way I would be able to tell every single difference between one gear with another. Comparing gears side by side the ultimate way to know which one is the best. Happy Listening!


My uDAC-2 has stopped working properly. It produces crackling sound everytime I listen to high pitch female voice. I now consider it dead. It’s only been 3 years. 3 year old. And it’s dead. I think this is a great example why we all should only purchase well engineered items.

Audio-gd isn’t a well known audio company brand in the US yet!. The company is led by Mr. He QingHua (Kingwa), the First Prize winner of the American National Semiconductor Audio Design Contest. Kingwa designs his gear based on his  extensive research on high end audio equipments. He’s been listening to his customers all along, including following discussion threads at many audio forums. There are three products that came to fruitions because of customers’ demands; first the Compass (Amp/DAC combo), the Panther (a power amp), and the Phoenix (a fully balanced headphone amp/pre-amp).

I’ve been using the Audio-gd DAC 19Mk3 for a few months and I‘m very happy to report that this is my favorite DAC, compared with:

  • NuForce uDAC-2 ($129 USB DAC)
  • Mhdt Havana ($749 ~ typical NOS DAC sound signature, sounds warm and pleasant)
  • Pico amp/DAC ($499 ~ small, err… tiny, there is nothing wrong with the SQ considering its’ size :D)
  • AMB Gamma 2 ($230-parts cost only ~ superb DAC for its’ small size, my second best DAC, it sounds neutral, you can also drive a headphone from one of the analog outputs)
  • And, a few other famous DACs…

I tend to buy a few things at the same time for my curiosity sake. If I don’t like it, I can always sell it or return it. I’m pairing the Audio-gd DAC-19Mk3 with Audio-gd P-2, D-Sonic Magnum 500S (2X250W / 8Ω | 2X500W / 4Ω; ICE Power), and Selah Audio RC3R (3 way monitor; Fountek ribbon tweeter, Morel dome midrange and Scan-speak woofer).

The DAC-19Mk3 uses two Burr-Brown PCM1704UK – R-2R/multi-bit chip, one chip per channel. It’s a single ended DAC with two sets of RCA outputs. The PCM1704UK is considered to be the best sounding DAC chip. Manufacturers are now favoring Sigma-Delta chips due to its ease of manufacturing (cheaper to produce) and features that can be implemented in the chip (built-in digital filters, anti-clipping; take a look at Wolfson’s top of the line DAC, WM8741 that can be found in PS Audio PerfectWave DAC). They no longer consider sound quality to be the top priority in making those chips. Those claims above may be argued by some people, but the PCM1704UK is still used by some of the best DAC designers and the chip can be found in some of the most expensive DACs. The D/A chip is irrelevant to judge a DAC unit sound quality, what really matters is its’ implementation.

There are two digital filters can be used in the DAC-19Mk3, the Pacific Microsonics PMD100 (a 24/55 HDCD digital filter) and the Burr-Brown DF1704 (a 24/96 digital filter). All the processing/filtering after the DAC is done in the current mode – ACSS which is a lot less harmful to the sound than voltage mode. Each PCM1704UK has its’ own ACSS module. The Audio-gd ACSS technology is inspired from Krell who is the proprietor of the current gain technology. It has zero feedback analog stage, DC coupled, and discrete output stage – there is no op-amp, no coupling capacitor on the signal path.  to purify dirty power and provide the cleanest power to the digital board and analog stage. There are two beefy R-Core power transformers, each of them serves different purpose, one for the digital board and the other one for the analog stage. They are carefully shielded. Those are not marketing hypes, they are just good designs.

It has 3 selectable inputs: Coax (RCA), Optical (ToSlink) and USB. One can ask Audio-gd if one needs different (Coax RCA – BNC) or more inputs. The USB input uses the commonly used PCM2707 USB receiver to convert the USB signal to S/PDIF. I have read a few decent articles that claim i2s signal is better for USB input. I used it once for my curiosity sake and the sound was decent. I don’t really care about this as I rarely use the USB input. I also found out that the DAC-19Mk3 is able to output ACSS (CAST) signal if needed, you just have to swap one set (there are two sets of RCA outputs) of the RCA outputs to ACSS (CAST – 4 pin) outputs. That if you own an amp or a pre-amp that accepts ACSS (CAST) inputs. For those who will be using the USB input exclusively, you might be interested in shutting down the S/PDIF inputs when using the USB input by installing a jumper to get an improved SQ. Here is a picture to show how to do it:

Let’s see where this DAC excels! The power supply is monstrous, Kingwa designed the DAC to have superb power filtration. It has 8 groups of parallel Class A voltage regulators to purify dirty power and provide the cleanest power to the digital board and analog stage. The noise floor is suppressed to the lowest level possible – no audible noise at all. Sub-par products tend to perform mediocre when fed with dirty power due to their poor power supplies. Switching power supply is also a big no-no, a regulated one is generally preferable for high end audio electronics. Clean power is very essential for any audio or electronic products, insufficient power filtration may produce bad results and also shorten the life of the circuits. Almost half the size of the DAC-19Mk3 is used for the power filtration, one does not need to worry about getting a power filtration/regenerator unit or a fancy power cord (snake oil!).

~ I tried various power cords for my curiosity sake, none of them improves the SQ or sound different. I have also tried various interconnects from Blue Jeans cable, ‘SPC (silver plated copper) sponsor’ cable, Cryo-parts SCSCag wires, all of them sound exactly the same. Unless your cables are mediocrely built, I don’t see the point of buying these fancy cables other than for their looks. All these expensive fancy cables are merely jewelries that do not add anything to the music ~

DAC-19Mk3 without digital filter board and ACSS modules installed

The Sound

About the SQ… it’s a superb DAC. This DAC completely surprised me during my first listening session with a whole new set of audio gear. I have always thought that the Audio-gd Phoenix (headamp/preamp) is no where as dynamic as some of the best headamps out there, I thought similar sound signature could also be found in the DAC-19Mk3. The single ended Audio-gd DAC (19Mk3) is well, different. It is very dynamic and at the same time, not harsh at all. This DAC makes me appreciate good recordings and instruments. There were times when I thought certain instruments sounded weird when played directly from my sound card, a PS3 and an iPod; the 19Mk3 corrects all faults in my system, every single instrument sounds right to my ears. The vocal is silky smooth, it does not have any digital trace at all. The soundstage is huge, grand soundstage. You won’t get the DAC-19Mk3’s soundstage and incredible dynamic with a NOS DAC, its soundstage is a lot smaller than what the DAC-19Mk3 can produce, NOS DAC also sounds recessed, very recessed if one compares them side by side. Now, I understand why some people like NOS DACs’ sound signature, it’s easy on the ears. The DAC-19Mk3 sound placement is superb, it is never in-front-of your face, it’s like hearing a live performance! The background is very black, one can easily notice tiny details in the recordings. There are layers of details, one can easily pin-point instruments that are playing. This is the most analog sounding DAC that I have tried. Everything seems to be natural, dynamic, and very well balanced. I couldn’t find anything wrong with the SQ. The bass gets low and impactful. I am honestly amazed by this DAC, it is a giant killer. The DAC-19Mk3 is quite neutral, this is a plus: good recordings would shine, but bad recordings were still bearable or even enjoyable if one liked the music enough to accept the poor recording. Being a music fanatic first and audiophile second, I tend to listen to a number of poor recordings as well as very good ones. 😎

If I were to point out areas where I want the 19Mk3 to be able to do a little more is the bass impact. I’m not a bass head, perhaps my transports aren’t good enough (Arcam CD36, Squeezebox Classic, and M2Tech hiFace) but I have not been able to find any major sound quality difference between them. I don’t see the need of getting a big and expensive transport unless my current transport is very bad and affecting my system’s sound quality.

I’m very impressed with Kingwa’s attentions to details, every single part of the DAC seems to be well thought out. I’m also amazed by Kingwa’s decision to salvage any (Pacific Microsonics) PMD100 from used audio equipments. PMD100 is no longer made and is getting rare to find. As mentioned above, I can choose to use one of two excellent digital filters, the musical PMD100 and the neutral (hi-fi) DF1704. The PMD100 produces musical sound signature which suits classical, jazz, female voices, basically anything slow. If I want more impact and neutral, I use the DF1704. The bass has noticeably increased, it goes deeper, and produces more details but the soundstage seems to suffer. PMD100 (laidback) is preferable for forward sounding speakers while DF1704 (forward) is better for laidback speakers, it’s all about balance and synergy.

Audio-gd PMD100 board

Build Quality

For those who care about the build quality and chassis work, the innards look quite good but it’s definately not at the same level of finesse of HeadAmp (Justin Wilson) which I consider to be one of the very few manufacturers who craves for perfections. There is a few major concerns about the build quality and there are some minor imperfections, such as: a few not-so-good soldering jobs, bent PCB, many traces of glue on the PCB, and parts are not aligned as neat as HeadAmp. This DAC looks almost like a DIY unit. My AMB y2 looks much better inside out. The chassis is as simple as it can be, it works and it is very sturdy but it’s far from a Grade A chassis. The plates are not aligned perfectly, there are gaps between plates here and there. My DAC-19Mk3 top plate is hard to pull out due to incorrect size of the top plate. These are just some minor shortcomings that have nothing to do with the sound quality. I would rather have a well designed innards than a beautiful chassis that may cost up to half the price of the unit and skimp on the quality of the components inside.

This is one hell of a DAC. I can’t imagine how good higher end Audio-gd DACs are after using this DAC. I bet it’s a huge step up above the DAC-19Mk3. This DAC is priced at $480 + shipping. I don’t think I can find any better DAC at that price point. All brand names DACs that I have auditioned above are not even close to the DAC-19Mk3. I don’t usually buy ‘Chinese’ products if I have the chance to choose. Off course, almost all electronic products are now made in China, not that it matters but I had a sheer experience of buying unknown ‘Chinese’ made products that failed to meet my expectations in the past. This is simply not the case with Audio-gd, superb designs, superb executions and zero marketing BS (unlike many major brand names who sell more marketing that the actual product itself :mad:). Thanks Kingwa, for making this excellent DAC! Oh and, you might want to pick the PMD100 as the digital filter or your super backup, the supply is running low. If you send an email to Audio-gd, don’t be surprised by their difficulties of answering questions in English. They usually reply within hours.