I upgraded to an Aqua La Voce S3 DAC recently so this is for sale. It is in perfect condition and works flawlessly. It ships in the factory box with all the literature. My asking price of $900 is firm, a bit under 50% of the retail price of the DAC. I will absorb PP fees and shipping in the CONUS.
It can be used as a stand-alone DAC, headphone amp, an/or digital preamp. It is an improvement over the original Ayre QB-9, which is outstanding, and it is more versatile. Here is a an excellent review:
https://www.stereophile.com/content/ayre-acoustics-codex-da-headphone-amplifier-page-2 
