It’s no surprise to see a motherboard, vga, notebook, or even a barebone PC from ASUS. But, wait a second, a sound card? Yes, a sound card. ASUS introduced Xonar D2 (PCI) and D2K (PCI-E) sound card on CeBIT 2007, few months ago.

This sound card is equipped with Dolby Digital Live and DTS Connect. These two features allow Xonar to stream any sources in the Dolby Digital or DTS digital signal. So, you can connect this Xonar to your receiver via one digital cable only. Any sources means MP3, MPEG, DiVX, etc (any non-multichannel audio). You can enjoy multichannel audio by activating this feature. So I guess, Xonar is expected to become a nice HTPC companion.

The photo above shows the PCI version of ASUS Xonar, while below is the PCI-E 1x version.

ASUS is well known for its good relationship with Analog Device. So expect to have Analog Device (ADI) DSP on this card. This card claims 118 dB playback and 115 dB recording Signal-to-Noise Ratio (SNR). Really an excellent number! Xonar support 7.1 and 24 bit 192 kHz audio capability (both playback and recording). ASIO 2.0 also supported. Other features included are Dolby ProLogic IIx, Dolby Virtual Speaker, and Dolby Virtual Headphone. According to ASUS, this card measured at 0.000006% THD (so many zeros! ;)) on its eight channels and single line input.

The photo above shows the card with no “EMI shield”. We will discuss about it later. While the picture below is the card with EMI shield. Please take note that the black plate on the top is not a heatsink, but an EMI shield.

About “EMI shield”:
As we already know (if you havent then please continue), PC is not a good source of music. Inside the PC (inside your case) there are a lot of noise. Noise from your power supply (switching PSU on computes is not a good source for audio), noise from your dozens fans, noise from your motherboard, noise from your VGA, etc. This noise may affect the overall sound quality. How to eliminate it? One of the common approach is to use external solution (USB or FireWire sound card). Many professional audio already follow such approach. But since we are talking about consumer thing, let’s keep them inside your case and forget about external card;)

Another approach is to use a plate as shield. This shield (like the one used on this Xonar) is used to isolate the card from outside noise (EMI is one of them). By doing such approach, we can expect better sound quality (less noise = higher quality). Other sound card manufacturer like Audiotrak (Prodigy Hi-Fi) and Onkyo (SE-90PCI, SE-150, SE-200) also use the similiar approach. All of them get positive result. No surpise if ASUS also tries the same way to achieve better sound quality. Read more here about audiophile’s sound card.