The New Recommendation: The Yulong U100 USB DAC
The Audinst HUD-MX1 has been the reigning champion for a $100-$200 DAC/Amp box, but now it has gotten a new challenger. After having used the Yulong U100 for a few months, and comparing it to the Audinst, I think I have a new recommendation for people looking for an entry level DAC/Amp box, though costing a bit more ($180 for the Audinst vs $240 for the Yulong U100).
I received the Yulong U100 from Jeffrey at coolfungadget.com, and at that time he sent me the Yulong U100 along with the Musiland 02 DAC. Upon receiving the product, I played around with both units briefly, but the Musiland with its upsampling feature and software controls were more exciting than the plain DAC/Amp box Yulong. And so I wrote about the Musiland 02 article very soon afterwards, while the Yulong stayed pretty low under the radar.
It’s logical to not get excited about the Yulong. After all, it doesn’t offer anything new to the table. It’s just another USB desktop DAC/Amp box solution coming from China. And frankly, there are just too many of them these days. To make the case worse, I’ve also been spoiled with too many higher end solutions lately.
I tried really hard to readjust my ears. One of the things that I did was to listen to the $130 Musiland 02′s DAC section and compared it to the Yulong U100. Turns out that my enthusiasm with the Musiland 02 as a DAC/Amp box (not counting its upsampling feature) dies off pretty fast once I did the comparison. The Yulong is definitely better. I needed a stronger competitor, and so I began to compare the Audinst HUD-MX1 to the Yulong. After all those evaluation times (good think I don’t have any deadlines for this article), I’ve finally gotten the sound of the Yulong and now it’s time to write the article.
I would be lying if I say that the Yulong is the new giant-killer DAC/Amp box. But please don’t look down on it, because it just happens to give enough improvements over the Audinst HUD-MX1 that I think it’s going to be a great entry level DAC to recommend to people. For $60 more, you get a better sounding DAC/Amp box and with a prettier packaging too! It’s a bit larger than the Audinst, but on my desk, the Yulong looks like a nice piece of HiFi equipment, while the Audinst looks more like a computer accessories.
Based on the Cirrus Logic CS4398 D/A chip, the U100 clearly gives me a better sound when compared to the Audinst’s. The only drawback seems to be soundstage width, where the Audinst is wider. But for everything else, such as soundstage depth, center focus, ambiance, detail retrieval, midrange quality, the Yulong is better. Those gotta worth more than the $60 difference between the two products.
On the headphone amp section, the use of PZT2222A and PZT2097A transistors provides a much more potent headphone out than if I were using the Audinst’s. The level of articulation in the treble, mids, and bass, is clearly superior compared to the Audinst, both driving a Senn HD650. The Yulong also drives the same headphone to much louder volumes than what the Audinst is capable of. There is simply no competition here.
You can get a little closer to the Yulong U100 if you were using a fancy opamp like the OPA627 on the Audinst. Instrument separation, articulation and mid clarity would improve. But I still find the treble and bass separation to be a little muffled in comparison to the Yulong.
What about line out signal quality? Passing the signal to a HeadAmp Pico Slim and out to the JH16Pro, again I find the Yulong to give a clearer signal through the line out, better separation, better articulation and such. Perhaps the fact that the line out signal doesn’t get passed through the analog potentiometer (unlike on the Audinst) also adds to the superior line out quality of the U100.
In terms of tonal balance, the Audinst is slightly darker while the Yulong is slightly brighter. “Slightly” is the word to notice there, as both are still well in the realm of neutral. The only time I prefer the Audinst’s headphone out is when I’m using a relatively light-bass headphone like the HD598. But even then, the superior articulation on the U100′s bass brings me back to the Yulong time and time again.
One thing that I really enjoy is the vocal presentation on the Yulong. I am not a big vocal fan, but the vocals on the Yulong just captivates me. It matches beautifully with the HD598 and the HD650. The vocal is quite forward, giving me a good presence without being glaring. It’s very clear and with a slight touch of warmth. Definitely one of the most special vocal presentation in the price range.
Of course, the U100 is not totally superior on all aspects. For instance, I love the fact that you can use the Audinst without a separate power supply as it takes the 5V it needs out of the USB bus. The U100, on the other hand, requires a power adaptor, and that does come out as a negative for me (I love simplicity). Next, the Audinst comes with a dual output: 1/4″ and 1/8″, so that you don’t need to use an adaptor between headphones and IEMs. The U100 only comes with a 1/4″. Yes, it looks more “serious” that way, but I probably would add in the 1/8″ for the sake of convenience, if I was designing the product. If I were using an IEM, the Audinst gives me better control range on the volume, where the Yulong is more limited due to the higher gain level. Lastly, the Audinst comes with rollable opamp and optical S/PDIF out where the U100 doesn’t. This may be important to some, and less so for others.
Looking inside the enclosure reveals a very clean PCB layout, indeed a very refreshing look compared to the cramped Audinst. I’m not saying one is better than the other, but the Yulong is just nice to look at.I find a Tenor TE7022L chip that handles the USB data, and next to it is the Cirrus Logic CS4389 D/A chip. Two separate ADA4075-2 opamps serve as an output stage to the D/A chip, and finally passed on to the four 2222A amplifier chips before finally reaching the headphone out socket. The potentiometer used is a Taiwanese brand Alpha, which gives a nice stepping effect unlike the regular smooth turning pots you see normally. There is also an analog line in by the means of a tiny 3.5mm jack which gives you an option of using a different source (say an Ipod) with the U100.
I think the build quality of the Yulong is really worth mentioning. It’s one of the nicer looking builds I’ve seen coming out of China, and definitely better than the Audinst HUD-MX1. The chassis is anodized aluminum all around, with a thick front plate of 5mm. The anodizing quality is not quite on par with something from Ray Samuels or Burson, but for a $200 product, the finishing can be considered one of the best. The volume knob feels solid and the ribbed pattern feels very nice as well. Overall, I would get the Yulong over the Audinst just purely based on the superior build quality and pay the extra $60.
One thing that I have to mention is that the USB connectivity doesn’t seem to be as robust as the one on the Audinst, or all the other Mac-compatible DACs. Sometimes, plugging in the Yulong to my MacPro will immediately give a “bleep bleep bleep” sound on the headphones, the sound that you get when you’re hitting the volume level button on your Mac. Unplugging and plugging the USB cable back would solve the problem, so it’s not a big deal, but I am obliged to tell you about it. It also helps if you’re using a USB cable with ferrite magnet on it. I don’t know why this is, seeing that both the Audinst and the Yulong comes with the same TE7022L receiver chip. Moreover, on my Mac, the Yulong is only recognized as a 48/24 USB device, though the TE7022L receiver should be good for 24/92.
Warning to Mac Users:
I have been having issues using the U100 with Mac computers. On my MacPro I can make the problem go away by turning on the computer AFTER the U100 is connected and on.
However, I haven’t had any success with my Powerbook and a friend’s MacBook.
So, I wouldn’t recommend it to Mac Users.
All pluses and minuses considered, I think I find far more pluses than I do minuses. So, if you can handle the extra $60, and you don’t need the extra functions on the Audinst, then the Yulong U100 is the box you should get for your headphones.
Gears used for review:
Headphones: Sennheiser HD650, HD598, Audio Technica M-50, JHAudio JH16Pro
Amplifiers: HeadAmp Pico Slim