Hi EdThats true, all of that is established theory. My intent was to simply make a point to Paul, as he said since multi-way systems cannot cover 20Hz to 20KHz either, then we may as well use a fullrange driver instead for that reason. I was just presenting a number of other things to consider other than bandwidth.
But everyone has their own opinions. Some audiophiles will argue that multi-way systems will smear the sound, whilst others will say fullrange drivers sound like clock radio's. Then others may simply choose a fullrange driver for fear that the designer of a multi-way speaker doesn't know what his doing with the crossovers (which elektratig brought up). IMO, it's a waste of time to try and change people's opinions, so instead we can discuss what does differentiate the two systems.
Adrian