Microphones: Polar pattern / Directionality

Microphones: Polar pattern / Directionality

The polar pattern of a microphone is the sensitivity to sound relative to the direction or angle from which the sound arrives, or easier worded how well the microphone “hears“ sound from different directions. The most common types of directionality are: Omnidirectional, Cardioid and Supercardioid

Cardioid

Microphone Cardioid Pattern
Cardioid polar pattern



A cardioid microphone has the most sensitivity at the front and is least sensitive at the back. It isolates from unwanted ambient sound and is much more resistant to feedback than omnidirectional microphones. That makes a cardioid microphone particularly suitable for loud stages.




Supercardioid

Microphone Supercardioid Pattern
Supercardioid polar pattern



Supercardioid microphones offer a narrower pickup than cardioids and a greater rejection of ambient sound. But they also have some pickup directly at the rear. Hence it is important to place monitor speakers correctly. Supercardioids are most suitable when single sound sources need to be picked up in loud environments. They are the most resistant to feedback.

 




Omnidirectional

Microphone Omniderectional Pattern
Omnidirectional polar pattern



The omnidirectional microphone has equal output or sensitivity at all angles, this means it picks up sound from all directions. Therefore the microphone has not to be aimed in a certain direction which is helpful especially with lavalier microphones. A disadvantage is that an omni cannot be aimed away from undesired sources such as PA speakers which may cause feedback.

 




Figure of Eight (bidirectional)

Microphone polar pattern figure of eight
Figure of eight polar pattern



A microphone with a figure of eight polar pattern picks up the sound from in front of the microphone and from the rear but not the side (90 degree angle). Microphones with this Figure of Eight polar pattern are typically ribbon or Large Diaphragm Microphones.




Symbols for Polar Patterns

Symbol  Richtcharakteristik
 Cardioid
 Supercardioid
 Figure of Eight
 Omnidirectional
 Halfcardioid
 Hypercardioid

 

INFO: Proximity Effect
Every directional microphone (i.e. cardioid, supercardioid) has a so-called proximity effect. This is created when the microphone moves closer to the sound source resulting in an increase in bass response and, hence, warmer sound. Professional singers often work with this effect. To test this out, experiment with bringing the microphone closer to your lips when singing and listen for the change in sound.