Dave, I'm not a De Capo owner, but I'm an audiophile and a good friend of Chris Younkman, our gracious moderator here, so I happen to listen to his De Capos all the time while I'm at his place sipping his esspresso, enjoying his single-malt whiskey, eating his organic cookies, perusing his extensive collection of TAS and oggling his beautiful wife. We swap a lot of equipment as well (but that's as far as it goes). So I have a good idea of how the De Capos sound and what drives them well.
The De Capos do have a tendancy to reveal any brightness or harshness in components very easily, they're very revealing like that, but I wouldn't say that they're bright in themselves at all. There is a slight, slight glare or something in the 2Kz range that I only notice when Chris complains about it, but we're told that the tweeter upgrade solves this. As a matter of fact, we are waiting for a pair that are scheduled to arrive at Chris's house the day before yesterday. As an aside, the Van Den Hul D-102 interconnect is a great one that attenuates the top of the treble a bit in the event of some harshness that you're waiting to be rid of.
There are some significant factors in why the De Capos might sound bright to the unaccustomed, and they have everything to do with the lesser amounts of bass, and particularily the way that it rolls off. Without a crossover to speak of, the De Capos roll off the bottom end pretty smoothly, *maybe* even losing a little ground as high as 60Hz (very much depending on your amp, apparently) and slowly descend down to audible, but not punchy bass in the mid 40s, at which point they seem to fall off completely. Herein lies the rub: many small speakers of similar size these days have a "bump" in the frequency response designed into the crossover around 50 or 60Hz that you get used to. Add to all this the fact that your average stereo store showroom is big, oddly shaped and has a dozen pairs of speakers scattered around the walls destroying your bass reinforcement, and then you have a system that lacks a lot of bass, and sounds tipped up.
Does that sound sound like it could be the case to you? Then the DCs definitely deserve a second audition. If you have a small or medium sized room, the De Capos make plenty of bass with the right amp (that you are not interested in), but I've heard some very nice, neutral sound with tubes and De Capos - not bright at all, but very clean and dynamic in the top end.