SPACED PAIR: ANY PAIR OF MICS PLACED AT ANY DISTANCE.
XY: USES TWO MATCHED CARDIOD MICS, THE HEADS NEARLY TOGETHER AT 90 DEGREES.
BLUMLIEN PAIR:TWO MATCHED BI- DIRECTIONAL MICS, HEADS TOGETHER AT 90 DEGREES.
MIDSIDE:CARDIOD MIC FACING SOUND SOURCE AND BI-DIRECTIONAL MIC PERPENDICULAR TO CARDIOD MIC.
DECCA TTREE:3 CARDIOD MICS FACING LEFT, CENTER, RIGHT WITH PANNING MATCHING POSITIONS.