Microphone Pick-up Patterns

There is a region around each microphone called the pick-up pattern, in which sounds are best captured. 

Microphones are specifically designed to create a specific pick-up pattern, each ideally suited for a specific use. It's important to know what the pick-up patterns is of each microphone you use, so you can select the best microphone for the situation.

 

Microphones can be grouped into two different types of pick-up patterns:

 

 

Omnidirectional Microphones

 

 

 

 

  

 

 

Omnidirectional-Pattern

 

Omnidirectional
Omnidirectional microphones have a pickup pattern that captures sound in all directions equally, making them ideal for recording ambient sound. Although omnidirectional mics will pick-up sound sources provided they are the same distance from the mic, they tend to be a bit more directional with higher frequency sound sources.

  • Ideal for capturing the ambient sound of a location
  • Available in handheld and lavalier configurations
  • Ideal as a lavalier when the actors needs to turn her head in the scene, as an omnidirectional lavalier will ensure her voice will not leave the pick-up pattern
  • Not ideal for use on a boom pole.  The purpose of boom mics are to isolate the actors' dialogue above the ambient sound of the location, and omnidirectional mics do the opposite

 

 

 

 

 

Directional Microphones

 

 

 

 

 

 

 

Cardioid-Pattern

 

Cardioid 
Cardioid mics are the first in the directional microphone category.  With an inverse heart-shaped pick-up pattern, cardioids accept sound in front of the microphone and reject sounds to the side and behind the microphone. Cardioids are available in both handheld and lavalier configurations.

  • Handheld cardioids are the primary mics used in performance - singers, lecturers, comedians, broadcasters - where the mic can be held within 4-6 inches of the performer's mouth.
  • Lavalier cardioids, because they are more directional, tend to reject more ambient sound than their omnidirectional counterparts, making them ideal for recording talent in high-noise environments.  Beware that if the actor turns his head, the sound quality will change as his mouth will move outside the pick-up pattern.  Fixing this discrepency in post is extremely difficult.
  • Cardioids are not often used on boom poles because the pick-up patterns is still too wide to isolate actor's dialogue.  Additionally, the proximity effect requires the actor to be within 6-8" of the microphone, making it difficult to hide on set.

 

 

Hypercardioid-Pattern

 

Hypercardioid 
Hypercardioid microphones are much more directional than cardioid, and are used in interior locations when the micrphone can be placed close to the actors.  The extended pick-up pattern enables them to be positioned farther from the subject, while still capturing strong sound.

Be aware that, due to the physics of how microphones capture sound, hypercardioid microphones have a lobe of sensitivity behind the microphone.

  • Hypercardioids are used on boom poles when recording sound in interior, low-ceiling environements.
  • Hypercardioids have a lobe of sensitivity on the rear axis that will capture sound, so be aware of mic handling noise and proximity to other sound sources, such as studio monitors, air handling systems, or any equipment that may be positioned behind the microphone.

 

 

Shotgun-Microphone

 

Shotgun
Shotgun microphones are tube-shaped interference mics that use ridges along the side of the microphone to shape the pick-up pattern into a very narrow shape.  Shotguns are ideal for for recording dialogue on set because they accept sound directly on axis with the microphone, while rejecting sounds to the side.

There are three types of shotgun microphones available: short shotguns, shotguns and long shotguns.  Each type is physically longer with more interference rills along the side, narrowing the pick-up area.

Shotguns are the primary microphone choice when recording sound on set as they allow the boom operator to postition the microphone to only capture the actors' dialogue.  Be aware that useof a shotgun requires precision placement to ensure the actors do not leave the pick-up zone of the microphone.

 

 

Figure-of-8

 

Figure of 8
Ribbon microphones, by their very design, feature a figure of 8 pattern that pick-up sound equally well on either side, while rejecting sounds to the side.  Most commonly used in the studio for broadcast interviews in which the interviewer and interviewee sit on opposite sides of the microphone, the figure-of-8 pattern is an outstanding choice whenever two people need to share one microphone.