The two π speaker definitely has more bass. But the one π probably has just a little clearer upper midrange in the overtone region.

If your room is very small or you have subwoofers, the one π is very nice. But the two π's have a fuller sound because of the lower bass. The two π towers produce very low bass. People that don't use subwoofers generally prefer the two π and two π tower speakers over one π speakers. But if you don't need the bass because you use subwoofers, you might prefer the one π speakers instead.