ASUS Xonar DX PCI Express 7.1 Audio Card
ASUS Xonar DX PCI Express 7.1 Audio Card
The Xonar DX itself is very small, with a compact PCB and PCI-Express x1 interface, making it suitable for standard and low-profile applications. While the Xonar D2 Ultra we assessed back in the Fall was built around the ASUS AV200 High-Definition Sound Processor, the DX utilizes an ASUS AV100 High-Definition Sound Processor rated for 192KHz/24-bit. Other differences include the trading off of a single Burr-Brown 24-Bit DAC (123dB SNR) for digital sources to a dual Cirrus-Logic configuration, with one for the front speakers (120dB SNR) and a second for the remaining channels (114dB SNR). Both Xonar cards utilize Cirrus-Logic 24-Bit DACs for Analog inputs, with the DX rated for 114dB SNR while the D2 Ultra offers 120dB at 192KHz/24-bits. Both models support the same Analog Playback / Recording Sample Rates as well as S/PDIF Digital Outputs (44.1/48/96/192KHz - 16/24 bit), with support for Dolby Digital and DTS. The Xonar D2 Ultra takes things higher with S/PDIF Inputs and ASIO 2.0 support.
The tail end of the card has Analog Out, In, Aux-In and Digital S/PDIF Out using a TOS-Link with the Line-in/Mic jack. The Xonar DX also comes outfitted with a Front Panel Header for headphone and microphone connections. Additionally, the Xonar DX requires supplemental power to operate, utilizing a four-pin floppy power connection. Some may find this a problem as some PSU units no longer come with floppy power connectors, such as the Tagan 1100w PSU used during testing. Ideally, ASUS should consider adding an adapter to the retail package, which may be more useful than a low-profile bracket.
One of the biggest talking points with this card is ASUS' approach to EAX 5.0 support, through DirectSound 3D GX2. ASUS claims the Xonar DX can deliver EAX 5.0 effects through software emulation. Thanks to Vista's Universal Audio Architecture, Vista users need a software solution for EAX 5.0 support, and ASUS believes the end results, whether achieved through dedicated hardware or software, are the same. Creative has made it clear that they don't believe ASUS can offer true EAX 5.0 support, but it's all relative in the end. Interestingly, while ASUS does this all neatly within the driver package, Creative forces users to install an add on software package called ALchemy, that is only free for X-Fi users. Audigy users have to pay to use ALchemy.