Good questions.

First, for the sake of discussion, let me define two categories of speaker: large (capable of full-range bass response) and small (less capable.) I know it's an oversimplification.

Personally I'd aim to put together a system comprised only of large speakers, where all of them had "flat" bass response down to below 30 Hz, run everything full range, and let true subs (4 in total) handle what is essentially only the LFE's. Unfortunately space constraints and budget prevent me, and probably most others, from accomplishing this.

However I am part way towards this goal, and in my main home theatre room am running large full-range arrays for all 3 front channels - and three subs. And while I hate to overuse the adjective, I can say that nothing beats the impact that you can achieve with full range speakers.

Having stated this own personal ideal you can guess that going to smaller and smaller speakers would be, for me, less than ideal. Where budget and space considerations come into play (as they always do) I would still aim for as extended bass as possible - coupled with electronics that would allow me to match up with each speaker's low-level ability.

I'm not saying that smaller 80 Hz speakers are in any way inferior. Or that you can't build an excellent system around them. It's just that having experienced both large and small set-ups, this is one of those rare occasions where size really does matter, in my opinion.

Besides, (and I know I'm generalizing) you can always get a large speaker to behave like a smaller one by slecting a higher crossover point. But the reverse is not true.

Regards.

Jeff Mackwood