The directivity of the microphone!

Directivity describes the sensitivity of the microphone to sounds from different angles. It is often represented by a polar pattern in specifications. In each schematic diagram, the upper part of the dashed circle represents the front of the microphone, and the lower part represents the back of the microphone.

Omnidirectional

Omnidirectional has the same sensitivity for sounds from different angles. It is common in recording projects that need to record the entire environment sound; or when the sound source is moving, and it is hoped to maintain good reception; the lavalier microphone that the speaker wears when giving a speech also belongs to this type. The disadvantage of the omnidirectional type is that it is easy to receive the noise of the surrounding environment, and it is relatively cheap in terms of price.

Single point
The common single-pointing type is Cardioid or Hypercardioid, which has the best reception effect for the sound from the front of the microphone, while the sound from other directions will be attenuated, which is common in handheld microphones. In karaoke situations, the extreme of this type is Shotgun.

Bidirectional
Bi-directional (Bi-directional or Figure-of-8) can accept sound from the front and back of the microphone, and there are not many practical applications.

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