Hi Martykl,
Thanks for your comments.
A dipole can be modelled as two monopoles separated by a path length (the wrap-around distance) with the polarity reversed on one of them. In fact, that's what a dipole is! Take a Maggie and build it into a wall, and on either side of that wall you'll have a monopole source.
It's true that a dipole does not have the same in-room behavior as two asymmetrically-placed monopoles, but both of them more closely approach the same desirable end result: Greater in-room bass smoothness. This is backed up by several AES papers, and I can dig up citations if you really want but frankly would rather not go to the trouble. My point is, their effect is similar enough to make them easily compatible in the crossover region.
Regarding equalization, if it's addressing a global problem then it will be an improvement throughout the room. If it's addressing a local problem, then it will improve the response in one location but may well make it worse in another. How big that "location" is depends on the specifics, but I agree it's not a head-in-a-vice thing.
Suppose in one location you have a +3 dB peak at 50 Hz, and elsewhere you have a -6 dB dip at the same frequency (this is not at all far-fetched with a single-sub system). That's a 9 dB difference. Equalization cannot fix the 50 Hz region at both locations simulaneously; it can fix one, but at the expense of making the other even worse.
Note that one worthwhile advantage of a distrubuted multisub system is that the variation in bass response from one location to another throughout the room is greatly reduced. So any remaining significant problems are more likely to be global, and therefore EQing them is more likely to be beneficial throughout the room.
What I've been talking about in my posts here is only one aspect of getting good in-room bass from a subwoofer system, but it's the one most relevant to integrating well with dipole main speakers.
Duke
Thanks for your comments.
A dipole can be modelled as two monopoles separated by a path length (the wrap-around distance) with the polarity reversed on one of them. In fact, that's what a dipole is! Take a Maggie and build it into a wall, and on either side of that wall you'll have a monopole source.
It's true that a dipole does not have the same in-room behavior as two asymmetrically-placed monopoles, but both of them more closely approach the same desirable end result: Greater in-room bass smoothness. This is backed up by several AES papers, and I can dig up citations if you really want but frankly would rather not go to the trouble. My point is, their effect is similar enough to make them easily compatible in the crossover region.
Regarding equalization, if it's addressing a global problem then it will be an improvement throughout the room. If it's addressing a local problem, then it will improve the response in one location but may well make it worse in another. How big that "location" is depends on the specifics, but I agree it's not a head-in-a-vice thing.
Suppose in one location you have a +3 dB peak at 50 Hz, and elsewhere you have a -6 dB dip at the same frequency (this is not at all far-fetched with a single-sub system). That's a 9 dB difference. Equalization cannot fix the 50 Hz region at both locations simulaneously; it can fix one, but at the expense of making the other even worse.
Note that one worthwhile advantage of a distrubuted multisub system is that the variation in bass response from one location to another throughout the room is greatly reduced. So any remaining significant problems are more likely to be global, and therefore EQing them is more likely to be beneficial throughout the room.
What I've been talking about in my posts here is only one aspect of getting good in-room bass from a subwoofer system, but it's the one most relevant to integrating well with dipole main speakers.
Duke