When to choose the directional or noise canceling microphone?

The main difference of the appearance between the directional/ noise canceling and the omni-directional microphone is that the former one has air holes on the bottom.

The air holes also receive sound, suppose T1 and P1 mean the time and the pressure when the front sound hole receives the sound. T2/P2 mean the data when the back air holes receive the sound. In one word, subtracting these two data we have the direction of the microphone. Therefore the unobstructed air holes are very important for the directional or noise canceling microphone; if the air holes are obstructed, the characteristic of the microphone will turn to omni-directional.

In the general conference, we can use the unidirectional microphone to only receive the voice of the speaker without the clapping from the audience. On the other hand, in order to record the only sound from the wild bird without other animals’ sound, we had better choose more professional and stronger directional microphone.

The noise canceling microphone is mainly applied to the mechanism that is very close to the speaker, such as headsets, walky-talky which needs to receive the user’s voice clearly without any other noise.