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 Polar Pattern

Cardioid Polar Pattern

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

Cardioid microphones

Supercardioid Polar 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 very resistant to feedback.

Supercardioid microphones

Omnidirectional Polar Pattern

Omnidirectional Polar Pattern

The omnidirectional microphone has equal sensitivity at all angles. This means it picks up sound evenly from all directions. Therefore, the microphone need not 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 results in less headroom for feedback.

Omnidirectional microphones

Bidirectional polar pattern

Bidirectional 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 (at a 90 degree angle). Microphones with this Figure of Eight polar pattern are typically rIbbon or Large Diaphragm Microphones.

Bidirectional microphones

Hypercardioid polar pattern

Hypercardioid polar pattern

Hypercardioid microphones offer an even narrower pickup than supercaidioids 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. Hypercardioids are most suitable when single sound sources need to be picked up in loud environments. They are the most resistant to feedback.

Hypercardioid microphones

Lobar polar pattern

Lobar polar pattern

The Lobar polar pattern of Shotgun microphones is the most highly directional. It has a very narrow lobe in the forward direction and rejects sound from other directions. They have small lobes of sensitivity to the left, right, and rear but are significantly less sensitive to the side and rear than other directional microphones. Due to the narrowness of their sensitivity area, shotgun microphones are commonly used on television and film sets, in stadiums, and for field recording of wildlife.

Lobar microphones

Half cardioid

Half cardioid

Microphones with a "half cardioid polar pattern" are usually boundary microphones that are mounted on a flat surface. They pick up sound in a cardioid manner only in the hemisphere above the mounting surface.

Subcardioid

Subcardioid

A subcardioid pattern is wider than a traditional cardioid and falls somewhere between a cardioid pattern and an omnidirectional pattern. Also known as “wide cardioid”.