Rock, "frequency-dynamic" isn't a thing per se. What is a thing though is intermodulation distortion. If you play music that contains simultaneous highs and lows, and you play it loud enough to operate the speaker in its non-linear range, then the highs get modulated by the lows producing unintended frequencies. This is IM distortion. The same happens BTW in passive or active antennas.
Moving to a speaker with wider specs is the answer. This may be a floor-stander or a more sensitive bookshelf.
Regarding multi-driver speakers, each driver is akin to an antenna. If the radiation patterns are not coordinated, then you end up with unintended directivity. This is why, with the active LFR1100, Ian was nearly driven insane coordinating the patterns of the various drivers.
John is right. All things being equal, less drivers results in better sound. But things are never equal. That's just fiction.
