The Asus Xonar Essence One is an external soundcard and DAC designed specifically for use with high end earphones.  This is designed for use by people with very discerning ears, if you are not much of an audiophile or only use $50 headphones you will be missing out on the benefits Xonar Essence One offers.  If you are quite willing to discuss the merits of unbalanced and balanced outputs however this device is worth investigating.  The quality parts contributed to the premuim price of $600 but they also raised the audio quality enough for the ears of the Kitguru reviewer who highly recommends this for professional musicians and audiophiles.

"Today we are looking at the latest ‘audiophile’ grade Asus Xonar Essence One external soundcard and digital to analogue converter. The Essence series of products have targeted the enthusiast and audiophile user now for some time, using high grade components such as BurrBrown DAC chips. Today we analyse the latest Xonar Essence One from ASUS in a very challenging environment, paired up with a flagship, limited edition Valve/Tube CD player and award winning Audeze LCD2 headphones."

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Audio Corner