A microphone’s polar pattern is the shape of where it hears. Cardioid, omni, figure-8, supercardioid — six common patterns, each one drawn out with a diagram and explained in plain English.
A microphone doesn’t hear all directions equally. The shape of where it picks up sound — and where it doesn’t — is called its polar pattern. It’s the difference between a mic that hears only you, a mic that hears the whole room, and a mic that hears front-and-back but rejects the sides.
The diagram below each pattern shows the “shape” of where the mic listens. The black dot in the center is the microphone. The shaded area is what the mic hears. Anything outside the shaded area is rejected.
Hears equally in all directions. Picks up the whole room. Used for: lavaliers, ambient room mics, conference tables.
Heart-shaped pickup — front yes, back no. The most common pattern. Used by: SM58, SM7B, most podcast mics.
Tighter than cardioid, with a small rear lobe. Used by: stage vocal mics that fight feedback, like the Beta 58A.
Even tighter, larger rear lobe. Used by: stage drum mics, on-camera mics.
Picks up front and back equally, rejects sides. Standard on most ribbon mics. Used for: face-to-face interviews, mid-side stereo.
Very narrow forward lobe. Used by film and TV shotgun mics like the MKH 416.
People obsess over what their mic picks up. The smarter question is what it rejects. A cardioid mic in a noisy room rejects the back of the room — the AC unit, the dog. An omni mic in the same room gives you all of it.
Live vocal singers want supercardioid because the wedge monitor pointing at them sits in the rejection zone. Conference rooms want omni so people don’t have to lean toward the mic. Ribbon mics use figure-8 to capture two singers facing each other on the same mic.
Some mics offer multiple patterns on a single body, switchable with a knob. This is a feature of higher-end studio condensers. Examples: