Filtering & shielding

Filtering

The Essence STX has arguably some of the highest quality capacitors seen at this price point.

The power input section after the Molex connector contains Panasonic Os-Con capacitors used mainly by audio gurus for modifying and improving existing designs.  They are arguably some of the best filtering capacitors available for audio design.  Other sections of the card contain Nichon fine Gold capacitors again very high quality audio filters used in priority locations on the card. 

EMI/RFI Shielding

The Xonar Series of cards all come equipped with EMI/RFI shielding over the sensitive analog components.  This shield prevents any EMI/RFI in your case from adding interference and noise to your audio signals and eventually to your outputs. 

Above is a shot of the card with the EMI.RFI main shield removed and place over top.  Unlike other Xonars the shield on the STX covers the most sensitive analog amplifiers circuits instead of the entire card. 

At the very end of the main removable EMI shield there is also a copper faraday barrier that isolates the power conditioning circuitry from the sensitive analog amplifications circuits.

From an electronics perspective, ASUS really pulled out all the stops on this card and included such shielding and other items just to keep the signals as clean as possible.