In terms truth of tonality and overall music reproduction ATC is among the absolute best. It is a true reference if you want to hear the tone and timbre of an instrument or voices. The active version is in fact spectacular. I cannot see any reason why anyone buys a passive ATC because in its active avatar it sounds far superior to any passive ATC + amp combo.
Acoustic Zen is among the most colored speaker of the three, so take your pick.
Acoustic Zen is among the most colored speaker of the three, so take your pick.