Active speakers offer some opportunities that a lot of passive speakers do not or cannot. For a passive speaker to be time aligned the voice coils of the drivers would need be on the same plane. That is to say that the tweeters would therefore need be recessed. A box speaker where you can see this is Lipinsky. Or, speakers with their tweeters recessed in a guide ala AudioKinesis. Vandersteen mounts individual modules for his drivers no larger than they have to be to accomplish this and others cant back the top of their enclosures to get in the neighborhood. Active speakers do this in the crossover. I don't know about all but some active speakers will feature DIP switches on the back to give a listener DEQX availability to tailor the sound. I've read that Active ATC 20's are a favorite of some producer/engineers. I use Meridian M20 actives which offer this and depth of field is strikingly good when it is in a recording. They image like fiends and most always sound very wholesome in my system and setting. They are otherwise conventional box speakers. I attribute a bunch of that to them being time and phase aligned.
