But isn't this why the room acoustics is so important? One should not have to apply more than one filter to correct a resonance at one frequency if the room is doing its job! My belief is if you have to apply multiple filters for a narrow frequency spike or bump, it's the room or a very poorly designed sub driver or enclosure "ringing". Granted it still has to be corrected for the system to sound "right" but not multiple filters.
My engineering degree is not in acoustics, so this is just my opinion.
