[quote name='Bill Fitzmaurice' timestamp='1400858941' post='2457674']
Do it anyway, not for tone purposes, but to limit driver excursion below the useful frequency range and cut down on thump noise.
[/quote]
I normally run with the filter switched on anyway. For limiting LF driver excursion, wouldn't 75Hz be even better? It's 12dB/octave by the way.