I have tried this with Desktop R2R sources with Denafrips Ares II + Topping A90 combination. I own a Final D8000 and did AB-ing with D8000 and the EXT for some time... though unfair to compare and IEM with a full fledged Headphone. To my surprise, I have found the EXT to be much better performing for the tracks that I have tried. @Vision Ears EXT is worth every penny it seems!
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