We want to make it clear right from the start: ASUS Xonar Essence STX is primarily design for audiophiles and not for average users and gamers. This doesn’t mean that these type of users cannot use this sound card, on the contrary, but only when this sound card is used for listening to high-quality sound recordings on adequate equipment (headphones), its true values can be seen. Packaging emphasizes exclusivity which becomes even more obvious when sound card is taken into hands. EMI (Electro Magnetic Interference) shield is first detail that anyone will notice. Black shield with ASUS logo looks nice but more importantly it protects components from various interferences that can be inducted inside the PC chassis by other components. Another feature that distinguishes ASUS Xonar Essence STX from most of other sound cards is presence of molex power connector.

It is nice to see that we are finally moving away from old PCI heritage. This sound card uses PCI-E x1 slot. On the PCB of ASUS Xonar Essence STX are also present additional pins that are used for front panel audio connectors. Back plate is dominated by two big 6.3mm stereo jack connectors. One is for headphones and the other is line-in. Beside those, there are also two mono RCA jacks for speakers and S/PDIF connector that can be coaxial or optical (TOSLINK) if small adapter is used. Beside the card itself in the box, we also found CD with drivers, Y cable that transforms two mono connectors into one standard stereo jack and adapter for 3.5mm jack that can be used for headphones or line-in.

There is only one word that can describe manufacturing quality of this card: perfect. It is almost unbelievable how ASUS managed to pack such quality components into functional product for such a low price. One of the main problems when it comes to sound reproduction in a PC is a lot of interference that can occur inside PC chassis. Beside already mentioned EMI shield, ASUS engineers used multilayer PCB that allowed them to properly ground all noises and achieve better protection for signals inside the card itself. For all audiophiles one of the details that proves quality of this sound card are Burr-Brown DAC (Digital-to-Analog Converter), Nichicon “fine gold” capacitors and bug purple Os-cons Sanyo capacitors that are known for their high quality signal filtering.  Main processor used on this sound card is C-Media 8788 chip that was renamed into ASUS AV100 High Definition chip. How meticulous were ASUS’ engineers when they were creating this card can be noticed by presence of removable Operation Amplifier chip. This chip is, among other things, responsible for “colorization” of sound so every user can adopt it to its own taste. After all these technical “stuff” we should proceed to most important segment: acoustic test.