Still observing the same minimum six-foot distance rule, another approach entails using a stereo pair of matched cardioid microphones, usually condensers (though it’s not entirely essential that they be so) to capture a stereo image of the drums from out in the room. Arrange the two mikes in an XY pattern facing the kit (FIG 2). The closeness of the capsules eliminates time arrival differences between the two room mikes, making this array very phase accurate.
Fig. 2: XY Arrangement Of Two Small-Diaphragm Cardioid Microphones
While this arrangement sacrifices a little width in the stereo image (as opposed to that captured by a near-coincident or split pair), the left and right channels will collapse to mono without funky phase issues degrading the sound. If you want a more expansive room sound, you could try a Blumlein array. This is a similar coincident pair technique that simply replaces the cardioid mikes in the XY pattern with bidirectional ones to achieve a broader stereo image and capture even more ambient reflections from all around the room without sacrificing mono compatibility (FIG 3).
Fig. 3: XY Arrangement Of Two Large-Diaphragm Bidirectional Microphones (Blumlein Array)
The boundary microphone, or PZM (pressure zone microphone) as it is often called, is the proverbial fly on the wall of the recording studio. You can opt to use a couple of these little buggers instead of overhead mikes to capture the sound of the room and the brightness of the cymbal wash. These low-profile flat mikes can be mounted to plywood and hung on the wall, or, if the drummer’s back is to a window, they can be taped to the glass about six feet behind and above the player, spaced apart to get a stereo image. If you want to capture more lows, you can try placing a PZM on the floor about six feet or more in front of the kit to pick up more bass drum. Just be sure that the flooring of the room is a hard surface and not carpet.
Fig. 4: A unidirectional mike pointing up at the corner of the room picks up only reflected sound. The sound must thus travel farther before it hits the mike, giving the sonic illusion of a slightly larger room.