M80s are listed at +/- 3db all the way down to 34 Htz so that's pretty capable in the low end. If your crossover is set to 80 Hz, then very roughly, everything from 80 Hz down to 34 Hz would be produced from both speakers.
Edited to say:
but that shouldn't mean you don't need a good sub. Setting a crossover and setting your mains to small lets the subwoofer handle the lows as it can
-- less effort,
-- maintain the proper volume levels even at Very low frequencies (sound levels drop of very ver quickly after M80s hit their 34 Hz limit)
-- and may even keep the bass cleaner at the extremely low levels.
It also frees up your mains so it they can concentrate on what they do best.
Last edited by Murph; 12/16/08 06:47 PM. Reason: clarity
