Concluding my review of the first product from ASUS’ sound card department Xonar D2, I wished there had been a Deluxe version of it that would have employed the best-quality digital-to-analog converter from Texas Instruments called PCM1792A. When I was writing that conclusion, there had already been released the PCI Express version of the card, Xonar D2X and the two low-profile cards Xonar DX and D1 were getting ready to be announced. They used a design with a top-quality front output and lower-quality rear channels. As time went by, there was no information about improved versions of the Xonar D2 and D2X. A few months later, there appeared news on the Web about two HDMI-oriented sound cards from ASUS: Xonar HDAV1.3 and HDAV1.3 Deluxe. Was it the Deluxe I had waited for? No. When I scrutinized the specs, descriptions and photographs, I saw that the analog section of those cards differed from the Xonar D2 only in the opportunity to replace operation amplifiers without soldering. Quite disappointed, I gave up keeping track of ASUS’s new sound products especially as there was in fact no news about them for a while.

It had been a lull before a storm, actually. The first news on the Xonar Essence STX really stormed through the newswires, leaving only totally deaf people indifferent. ASUS did more than I had expected: stereo outputs only, premium-class converters (a PCM1792A DAC and a CS5381 ADC), an integrated headphone amplifier based on the enthusiast’s choice TPA6120A2 chip, and electrolytic capacitors that had earned an excellent reputation in audio equipment. It is hard to believe but the Xonar Essence STX has absorbed nearly everything best from what is being discussed on audio technology forums. Now you can imagine how anxious I was to hear its sound. And here it is: a stern black box with a reproduction of an Ancient Chinese engraving and a message to audiophiles…

http://www.xbitlabs.com/articles/mul...sence-stx.html