Understanding Microphone Patterns

In the last post I discussed the two main types of microphones dynamic and condenser. Both of these types of microphones can have different patterns. Patterns describe how the microphone sensitive the microphone is to sound waves in relation to the space surrounding the capsule.

An helpful analogy that’s very imperfect might be a wide lens vs a telephoto lens. Some lens designs are better for some applications. For instance a shotgun microphone will be better a picking up sounds further away while an omni directional microphone will work closer to the sound source. This is true in most situations.

Let’s take a look at some microphone patterns.

First off, let’s look at the shotgun microphone. This is probably the first microphone a filmmaker becomes acquainted with. It’s the one you might see dangling at the end of a long boompole following the talent in a movie production. This pattern has some wonderful directional attributes. It’s good at what we call side rejection. It hears less of what’s happening on the side of the microphone and more of what’s happening in front of the microphone. Unfortunately this comes with some compromises. It also tends to pick up noise behind the microphone. This can mean airplanes when shooting outside or a crowd when shooting at a press event. It’s also less forgiving when the boomwork isn’t spot on. If the boom isn’t panning very quickly between speakers dialog will sound “off axis” or unnatural. There are different types of shotgun microphones with longer and shorter range that use the “interference tube” design with the slots down the side which help with the side rejection. An example would be the venerable MKH-416 short shotgun and it’s big brother the MKH-816. There are also mics like the Sanken CS3e that use a hybrid design utilizing the interference tube and some extra mojo that make it sound better in noisy environments.

The pattern of a shotgun microphone's sensitivity.
The polar pattern of a shotgun microphone

The omni directional pattern is accepts noise from any direction equally. A speaker can speak into the microphone from any direction without experiencing and off axis effect. This can be a benefit when recording music performances in a controlled environment. While this may seem a disadvantage in field production, many omni microphones are also dynamic microphones that experience rapid fall off and actually work fairly well in noisy environments. A great example of this is the Electro Voice RE50.

Omnidirectional microphone pattern

One of the best microphone patterns for recording indoors is the cardioid microphone pattern. This microphone has better rear rejection and therefore usually works better in reflective pattern. Schoeps makes a very popular cardioid mic and Sennheiser makes the very popular MKH-50. There are variations on the cardioid pattern including they hyper and super cardiod. They all serve their purpose and sound better in certain circumstances.

Posted on: February 13, 2019, by :