1. Give me the coherence of a single driver any day of the week. This coherence is due mainly to a lack of cross-over phasing problems in the critical 300-3000 Hz band. But then, the overall characteristics of a single driver full range system exactly match the music I listen to. If you are into big, loud and complex, you will probably disagree with me.2. The normal instrument range is for 40 Hz for a double bass to 4200 Hz for a piccolo. The normal voice range is 60-1500 Hz (assuming that the F5 in Mozart's "Magic Flute" is as high as it goes). The normal piano range is 28-4200 Hz and the Boesendorfer Model 290 goes to 16 Hz. The normal large organ goes to 16 Hz, but a few monsters, like the Sidney Opera House organ goes to 8 Hz.
Question for you -- Capturing the fundamental is fine, but don't you want to get at least the first two harmonics?
Bob