I've been wonder about the following:

It is typically said that bass tends to be non-directional (by that I mean around 60Hz to 20Hz-something a subwoofer would do). Is it true to say that the higher the frequencies the more "directional" they are? Would this have anything to do with how large a soundstage seems to be when listening to music/movies? Also, is this why some people recommend that mains be "toed-in" towards the listener?

Thanks,
Nert