ASUS Xonar U3 USB Sound Card Review

nVidia_Freak - 2011-06-14 17:46:25 in Sound Cards
Category: Sound Cards
Reviewed by: nVidia_Freak   
Reviewed on: July 10, 2011
Price: $52.57


With the push and mass acceptance of HD video came the push and mass acceptance of widescreen HD monitors, and so too, has come the push for HD audio. 5.1 and 7.1 surround sound speakers. Disregarding quality, these can be had for comparatively little from earlier in the decade, thus, they are much more attainable for the mass market than they once were. With this mass adoption of surround-sound has come the demand for the hardware to utilize it, and manufacturers have responded. Gone are the days of the outdated AC'97 chipset, and here are the days of built-in surround sound capable chipsets on even the lowest of low-end motherboards. This mass acceptance of HD audio has raised the bar for audio quality standards, and has made it significantly more affordable for those standards to be experienced. Additionally, more manufacturers have stepped into the HD audio realm and have begun to create their own audio expansion cards for users that crave more quality, by means of higher quality DACs and op-amps, and more functionality, such as that provided by hardware EAX and various Dolby technologies.

This movement has not been limited only to desktop users, but it has also grown in popularity with laptop/netbook users as well. Although today's laptops, tablets, and even netbooks feature these newer audio chipsets, size constraints have generally limited users to ordinary stereo sound. The push for surround-sound, however, is strong enough that manufacturers have taken notice and have started catering to mobile users with external, ultra-portable USB sound cards. These ultra-portable solutions lack true surround-sound support, however, some offer simulated surround-sound by way of Dolby Headphone technology, and this does a very good job for movies and games. One such manufacturer of one of these ultra-portable USB sound cards is ASUS. ASUS only recently ventured into making sound cards with its high-end Xonar line of products aimed at gamers and audiophiles. Most recently, it has created the XonarU3, an external, ultra-portable USB sound card aimed primarily at headphone users and gamers. Today I'll be testing it, but first, let's have a peek.


Closer Look:

The ethereal and wispy colouring certainly invokes a warm, fuzzy feeling inside, and, the box's black satin colouring and compact size almost manage to make a box seem cute and cuddly. All over the box, in various (fifteen!) languages, are plastered the main attractions, which are:

Along with the compact Xonar U3 are the driver CD, user manual, a laughably short USB extension cable, and an S/PDIF adapter. The Xonar U3 itself is a small device, though not too small to be lost in the largest of hands. It has a protective cap for the USB plug that is attached with a bit of nylon string to the body, and it also contains a key ring loop to bring the Xonar U3 everywhere without thought. The plastic, black gloss housing doesn't feel particularly durable, nor does it feel particularly brittle, and my only complaint about its physical characteristics is the gloss paint that presents oils, finger prints, and the most miniscule of nicks as though they were the stars of a hit television show.


Connection Type USB
Output Ports 1x 3.5mm stereo TRS, 1x S/PDIF
Input Ports 1x 3.5mm stereo TRS
Audio Chipset ASUS UA100
Chipset Bit-depth 16-bit
Chipset Sample Rate 48kHz
Output Signal-to-Noise Ratio (A-Weighted)
100 dB
Output THD+N at 1kHz
Frequency Response (-3dB, 16bit/48KHz input)
20Hz - 20kHz
Output/Input Full-Scale Voltage
2 Vrms ( Vp-p)



Information courtesy of ASUS available at


Installing the Xonar U3 is very simple. After plugging the U3 into an available USB port and installing the drivers, everything is ready to go. The U3 features a couple LED indicators, one red LED to indicate the line-out/SPDIF port, and two blue LEDs on the front of the unit to indicate whether or not the volume is muted. Curiously, these two LEDs are under what appear to be circular buttons that I would imagine to be very useful for controlling volume. Unfortunately, these are not buttons at all, but are simply indicators that are lit if the Xonar U3 is not muted, and off if it is. Lacking a media geared keyboard, the only way to adjust the volume of the U3 is within the driver menu. This is a minor inconvenience that really ought not to have been. Particularly if one uses a long extension cable, they would be in easy reach for quick volume adjustments.



Driver Setup:

If one is familiar with other products that use the Xear3D driver platform, such as Corsair's HS1 USB gaming headset, then one is greeted by a familiar sight when opening the Xonar U3's driver menu. Various indicators, buttons, and settings are placed for the various settings and features. Up top is a very narrow range visual equalizer if that sort of thing entertains you. Selecting the amount of audio channels determines whether Dolby Headphone is enabled automatically when headphones are in use. This makes sense, as there's no need to simulate surround sound for something that only has stereo imaging. There is a sample rate drop down menu, however, 48kHz is the only option. Mode buttons are off to the right side along with volume control buttons, one of which is labeled SVN, which stands for Smart Volume Normalization. Essentially what this does is bring every bit of audio information to the same level. Though this makes hearing quiet parts a lot easier without having to blast the volume, it does take diminish the dynamic range. For music this should definitely be kept off, however, for movies it might be somewhat beneficial if the dynamic range is significantly large.

Clicking the italicized 'i' on the menu bar brings up the technical information about the Xonar U3. Of special interest is that it looks like the U3 has hardware EAX support, granted only EAX 2.0. I will say, however, in my experiences, EAX options were not available or do not work when enabled in games. Clicking the '?' next to 'Audi Channels' brings up a screen that suggests how many channels should be selected for different types of applications. Finally, clicking the hammer icon next to 'Analog Out' displays a drop down menu to select the resistance load of the particular set of headphones and microphone being used. These are available so that no matter what you use with the Xonar U3, volume can remain consistent across the board. What these settings do is change the amount of supplied voltage to the output stage, with 32 ohm headphones receiving the least, and 64+ ohms receiving the most. This makes sense, because the more resistance is present, the more is needed to achieve the same amplitude.

The 'Mixer' tab gives access to individual input and output volume controls for the left and right channels, and also includes monitoring of input levels. The 'Effect' tab contains an equalizer and some reverberation sound effects. 'Karaoke' provides settings that act as specific EQ adjustments to facilitate the act of performing karaoke. Finally, 'VocalFX' contains various tweaks and gimmicks for the input stage.



To test ASUS' Xonar U3 I will listen to both stereo and 5.1 surround sound music, watch various movies in both stereo and 5.1 surround sound, and play various games that have surround sound audio.


Testing Setup:


Comparison Sound Cards


Having been accustomed to my Juli@ > Little Dot Mk. V > K701 setup for several years, I began testing with a rather indifferent attitude. I didn't expect the best sound, particularly considering how little there is inside, nor did I expect the worst. It is no longer, after all, the era of the ESS Maestro. Upon listening, however, I was rather surprised that it actually sounded rather good. I have quite a difficult time describing the sound of the Xonar U3, because I can't pinpoint any one particular audible sonic difference between it and ESI's Juli@. Though the DAC is only capable of directly handling audio no higher than 16-bits and 48kHz, those specifications cover the majority of what I and anyone else will listen to, and will certainly cover the needs of the casual user. Its lack of native ASIO support may also deter anyone that strains for the utmost in audio quality by means of using the clearest pathway possible, and I am in that group. Still, it will only disappoint those that manage to purchase it under the absurd pretense that it is a portable professional solution.

Games and movies are much more enjoyable thanks to the presence of the Dobly Headphone, Pro Logic IIx, and Digital Live technologies. AKG's K701 boasts one of the widest sound stages available out of any set of cans, and with the use of Dolby's tech that wide sound stage becomes so much more. These same technologies that helped Corsair's HS1 USB headset make movies much more enjoyable by making me feel more involved apply here as well, but the largest difference, mostly thanks to the K701s, is that games are incredible to play. Not only can I immerse myself visually in a game world, I can also immerse myself sonically in it. It's great fun and a huge joy that I haven't experienced in some years since I moved away from Creative's offerings with EAX. Had I been able to test the Xonar U3 in person before purchasing, using my K701s, I would have been very compelled to purchase it based solely on its gaming performance.


My experience with the Xonar U3 really showed how far average sound card technology has progressed. The fact that one piece of the chain toward very good sound quality can be had for under $100 and in such a small package is absolutely brilliant. Lack of bloated drivers thanks to the small footprint of the Xear3D drivers means there aren't any system slowdowns. The amount of Dolby tech, this is an ideal candidate for any mobile gamers and movie watchers. A lack of native ASIO support might scratch this one off the list of considerations if the best sound quality possibly is a concern, but the overall sound is very clear and enjoyable. The only truly annoying things that should be agreed upon no matter who's asked, is that the glossy paint is easy to mar, and the two LEDs that are in the perfect spot for volume control buttons, aren't. For approximately $55 the Xonar U3 USB sound card can be yours. For what it offers and at that price, there's no reason - especially for mobile users - not to grab it.