Thread: ASUS Xonar

If there's one part of the computing experience we've missed it's something really high-end for audiophiles. And we're not talking about the dime-a-dozen 7.l-channel cards. Just looking at the STX you just get the feeling of quality And it's hard not to get impressed looking at its spec-sheet. The 124 dB SNR aside, the functional parts (opamps, DAC chip etc) are covered with an EMI shield.

The Essence STX is built on a rather unusual four-layer PCB, ensuring excellent filtration of noise while the analogue output signal paths are also EMI shielded, ensuring that squeaky-clean signals are passed on. Additional power is RIl,\l\red via a four-pin molex connector. This one is built on a PCle xl interface and ASUS has recently come out with a PCI version.

The DAC is a Burr-Brown (now Texas Instruments) PCM 1792A, considered an audiophile-grade component. beneath the EMI shield the opamps are mounted on sockets as opposed to being soldiered to the PCB. This allows swapping of opamps walter the sound signature according to taste.

Note that the Essence STX is a stereo soundcard only, therefore it's special to see not one but three stereo opamps on the card. Two opamps are the JRC 2114, considered good for audio applications. These serve as the current to voltage converters and are placed just after the DAC chip. They utilise the output of this chip and convert its passing it on to the third opamp, the LM4562 which acts as the final buffer. Made by National Semiconductor, this opamp is quite famous and widely used by DIY audiophiles. Its claim to fame is excellent THD(Total Harmonic Distortion) quick slew rate and high bandwidth -all of these elements make for a superb choice for any discerning audience. Nichicon "fine gold" caps are used for all critical regions - a costly indulgence by ASUS and we highly approve.