Hi 4313B,
May be I do not uderstand your words, but I can imagine that almost Any decent speaker can be equalised to become respectable FR response, especially if power DSP support and multi channal amplifiers are applied. The problem can be the sound character of such system.
From my point of view, I woud not expect from multy-thousands U$D spekers would need additional sub-bass drivers, or enhanced DSP in order to produce acceptable sound reproduction.
I wonder what can be get from say old 43xx family speakers if DSP ,with FIR filters and time delay compensation including 4 chan.amlifiers being applied.
regards
ivica