I haven't heard the Ayon Audio S5 unit, but I have heard the AR REF DAC many times and I can tell you that if there is a better unit out there, I haven't heard it yet. For the prices of these units, they definitely warrant an in-home audition before purchasing. As I have mentioned in previous posts, something is seriously wrong if a potential customer wants to spend large amounts of cash on a product and the dealer will not let you take a unit home for a demonstration for a few days as least. They take your credit card information and charge it if you don't return it, so they can't lose. My favorite dealer in San Diego does this and I live in Los Angeles. I demo for a week or so and return it (usually drive down) if I don't care for it. So, I have a AR DAC 8 which Stereophile was totally wrong in their assessment as I found this to be a really great DAC and the REF DAC is heads above this one. It is really nice.
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