[boojum]

Originally Posted by audiothings

with blumlein, as i understand, the acceptance angle is 90 degrees, the front facing quadrant only... i do not know about phase cancellations and all, but if you setup a blumlein pair and say, circle around it while playing a triangle, you will find that when you are facing one of non optimized quadrants, the resultant recording will have a very haphazard and unreal movement between the speakers, and it will not be representative of the actual stereo field.

if you want 360 degree acceptance with a coincident pair, i think the only way to go is m/s with an omnidirectional 'm' (and of course, a bidirectional 's').

and now, to catch up with the stuff david pointed to...

I have tried MS with middling success.