The Polar Pattern of Microphones

Sound arrives at the microphone from all directions. However, a microphone might not be equally sensitive to sound from all directions. If it is, it is called an ”omni-directional“ microphone. Very common are microphones, that are sensitive for sound coming from the front, while sound from behind is (almost) blocked. Those microphones are called ”Cardioids“, because the graph, that shows the sensitivity as a function of the angle of the incoming sound looks a bit like a heart (heart is Kardía in the Greek language).

Imagine you look at the microphone down from above. Then you can draw a graph that shows the sensitivity of the microphone in each angle. If the graph is close to the center, the sensitivity is low. If it is far away, the sensitivity is high. The bottom direction stands for sound from behind, the top direction for sound from the front. The whole thing is called ”Polar Pattern“. There are very typical patterns:

Omnis: equally sensitive in all directions.
Cardioids: Highest sensitivity in the front, blocking sound from the back, attenuating sound from the sides.
Wide Cardioids: Highest sensitivity in the front, attenuating sound from the rear, but not completely. Sound from the sides is attenuated less then Cardioids do.
Super Cardioids: Highest sensitivity in the front, blocking sound back left and back right, attenuating sound from the rear. Sound from the sides is more attenuated than Cardioids do.
Figure of Eight: Equally sensitive in front and back, blocking sound from the sides.

A dashed graph means that the sound is captured with inverted phase.

You can listen to different patterns. Also: real microphones show a slightly different pattern for different frequencies. This leads to a coloration of the sound when it arrives from an angle that is not 0°.

Microphones
Choose out of a list from microphones. Choose ideal microphones if you want to focus on the pattern.

Choose non-ideal microphones, if you want to listen to off-axis coloration as well.

Frequency Response at

normalize

Normalise

If you want to listen carefully to the off-axis coloration, check this button. The pattern's inherent signal attenuation will then be balanced out.