Neobop, I don't have any experience working with Lowther or Audio Nirvana drivers. That being said, I'm in favor of doing things that produce a worthwhile net improvement, and if that means active or passive equalization then so be it. If you have a high output impedance amplifier, a Zobel could act as a gentle contour filter.
JLM, your DEQ approach sounds like it's been very successful. Nice job!
I understand what you're saying about bipolars being similar to omnis, but in my opinion there can be some important differences.
For the record, my bipolars do not try to simulate an omni. My bipolars give a more natural direct-to-reverberant energy ratio than an omni does (voices and most instruments aren't truly omnidirectional, but rather have mild directivity). My bipolars can be positioned and oriented to give a fairly long time delay before the onset of the additional reverberant energy yet can still be placed close to the side walls, so in many rooms they're more practical than an omni. My bipolars have never been accused of exaggerating image width like omnis do with some program material. Center image stability for off-centerline listeners is superior to that of an omni with a properly set up controlled-pattern bipole (I can explain why if you'd like).
Still, if we're putting speakers into broad categories, my bipoles could reasonably be lumped in with omnis and dipoles.
