It is true that powered speakers, particularly in the mid price ranges, can sometimes give better sound quality than passive ones -- for a very simple reason: they contain equalization circuitry in their amplifiers to compensate for the drivers used, which are usually relatively small and horribly inefficient. Henry Kloss -- the "K" in KLH -- pioneered this concept successfully years ago, with both the various KLH speakers and the AR (Acoustic Research) speakers -- both from the 1960s (you guys are all too young to remember them!). One does, however, want to take a look at them pretty carefully, as at the low frequency end, when they quit they quit rather abruptly -- and some of them don't go low enough to handle the low end of a piano, and just won't sound good. Any low frequency spec. higher than about 50 hertz is not likely to be satisfactory, and even that is marginal -- the lowest C on a piano is about 32 hertz.