I had the parasound d/ac-1100, which could have been "upgraded" to the pcm1704. But based on my experience with the M7, I did not go for it. The parasound with a cheap usb/spdif converter already sounded better than the M7 to my ears. But YMMV. Maybe you'll like the thicker, more syrupy sound of the 1704.
6/15/15 at 6:14am