Summary: A USB sound card can be a convenient and effective way to improve sound quality for a laptop or netbook, which might have less than impressive audio capabilities. The Xonar U3 USB sound card is a perfect example of this, and it just works extremely well for most of what it does. The power hum on the microphone input and the ineffective VocalFX were disappointing, but minor defects overall.
Pros: » Simple setup, » Easily portable, » Adds surround sound for headphones or digital output to a home theater, » Feature rich software adds value
Cons: » Windows only, » Audible power hum on microphone input, » Disables built in speakers
Conclusion: 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.
Pros: Lean Xear3D drivers, Various Dolby technologies at a comparatively low price, Surprisingly clear sound, Compact size
Cons: No native ASIO support, DAC only supports up to 16-bit/48kHz, No volume control buttons, Glossy paint blemishes easily
Summary: If your system has a free PCI or PCI Express slot, you'd do well to populate it with a Xonar sound card rather than filling one of your USB ports with the U3. The USB Xonar's signal quality simply isn't good enough, and its lack of high-definition audio support is difficult to ignore. Asus didn't intend for the U3 to end up attached to desktop systems, though. On its native turf in the notebook world, the newest addition to the Xonar family truly shines.
Summary: Após ter feito furor com a gama de placas de som para computadores de secretária, a Asus decidiu atacar o mercado dos portáteis que, como se sabe, estão bastante limitados na componente sonora, não só por questão de espaço, como do próprio consumo energético.