A while back my delightful sounding Denon DCD-3520 began acting up a bit. Intermittently, the display would cut out and the front panel controls, including the ever important "Eject" button, would become unresponsive, though oddly, all other transport functions seemed available from the remote, and that still worked. So while the deck still read discs perfectly, it became a crap shoot as to when and how I would be able to use it. So, for a time I hooked up my backup player, a Denon DCD-1520. While the 1520 is a fine player, and a credit to late 1980's CD players, it was not the 3520 with its commanding playback ability. As I was musing about the situation to AK'er MarkB, he brought up that he had a still new in box (literally) top-shelf Sony deck that he'd never used. Curiosity got the better of us, and since it became apparent that I would be bringing it home anyways, we figuratively decided to pop its cherry. This deck was, of course, the CDP-707ESD (CDP-557ESD to most of the rest of the world). TVK describes the 707ESD as the '.... origninal "7" series player ...' though that is contradicted on Axel's own site which pegs the original original "7" series player as the CDP-701ES, circa 1983-1985, a full couple years before the release if the 557/707ESD. Still, maybe it could be argued that the 707ESD was the first "true 7" series deck? :scratch2: In any event, we un-boxed the unit and hooked it up, marveling that there were still untouched warranty registration cards, an offer for 5 CD's for the price of one to bolster your CD collection, and above all, that the included batteries for the remote were still fresh, almost 24 years after it was first put in the box. As part of Mark's system (Yamaha CX/MX-10000 and Infinity Delta speakers), the Sony sounded absolutely marvelous. Like my Denon 3520, it possesses the qualities of Confidence and Authority (worthy of capitalization), but added to it a slightly better sense of "air" around the instruments, no doubt a result of a more thoughtful analog output stage. Technically, both the CDP-707ESD and DCD-3520 share a bit in common. They're both "statement-pieces" from the same era, use pairs of the same 18-bit DAC (Burr-Brown PCM64P), share similar approaches to construction (BMC/Gibraltar, copper-clad steel chassis overlaid with damped aluminum panels, discrete analog and digital/servo power supplies), and both use similar Sony transports and optical blocks. The real differences lie in the digital filters, which, while both 8-times over-sampling, offer a resolution of 18 and 20 bits respectively. Thus, I would expect similar audible performance, but each seems to have a slight, almost unnoticeable edge over the other in different disciplines. The Sony offerers a tad bit better imaging with a deeper, better defined sense of depth, and a high-end that is a bit more effortless. The Denon seems to offer a tiny improvement in dynamics, offering a little better definition when things tend to get loud (where many CD players tend to congest slightly). So, what I have here is a very well performing deck that, as of right now, holds the edge over my Denon for three reasons: First, it works as new (as it should); second, it offers a just-noticeable improvement in two areas that I give weight to (imaging and air); third, it just plain looks prettier. While I work at repairing the front panel troubles on the Denon, the Sony may not only fill the gap as only it can, but may actually usurp its position as top-dog, sitting in the rack. But, for some reason, I don't think that will actually be the case. It's always seemed to me to be a shame to let excellent gear just sit and wait because you don't have an immediate use for it (though, in my case it worked out very well indeed, as I got a brand-new, 23 years, 10-months old CD player), so I might actually expect to have both decks in the system, using them where I think they have the greater strength, even if it's only a matter of degrees.