What Are Microphone Polar Patterns?
Microphone polar patterns is an essential consideration, especially when it comes to considering whether a microphone is perfect or not perfect for a particular use.
The term polar describes how a microphone picks up sound and to be specific, it is a description of how sensitive a microphone is to sound waves that are coming from different directions.
So, in simpler terms, we can say that polar patterns refer to the sensitivity of a particular microphone to sounds that are hitting its central axis from different directions and angles.
Microphone polar patterns is a crucial component, especially in the film making industry. When making a film, you have to understand the different polar patterns, how they simply work and know the best areas to make use of them.
In this article, we are looking deeper into the different polar patterns and how they work.
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This kind of polar pattern is straightforward to understand. Omnidirectional kind of polar pattern is commonly referred to as omni.
Just as its name suggests, this omnidirectional microphone picks up sound in equal dimensions from all directions.
This means that, the direction that the microphone faces or the angle at which the microphone is placed is not a crucial factor.
The main factor that the user should consider most is the proximity of the microphone because it will determine how strong or weak the microphone picks the sound.
In the film making industry, omnidirectional microphones are the most preferred because you do not have to mind of the directions you are setting your microphones. You just place them for the recording, and you are good to go.
You are always sure that the received sound will be consistent even if the speaker is moving the head from side to side.
For a more natural and more realistic recording, you need an omnidirectional microphone.
However, it is essential to check the polar pattern graphics that are usually located in the specs section of the device so that you select the best omnidirectional microphone that perfectly meets your needs.
Bidirectional (Figure 8)
This bidirectional microphone is also known as figure 8. The microphone is among the three main polar pattern types of mics that includes omnidirectional and cardioids.
A bidirectional microphone usually has a figure 8 pick up pattern. The microphone sensitivity is generally two sounds from the front and back and rejects sounds from sides.
One of the unique things about the microphone is that the sound that is captured from the front side of the mic or the front capture is usually opposite in polarity to the sound that is captured from the back of the mic, that is the rear capture.
In the case of bidirectional microphones, the principle of pressure-gradient is the primary concept in the application. This means that the two sides of the microphone diaphragm are equally exposed to the sound pressure that is external.
In this scenario, a sound wave that is from the front of the mic would reach the front and the back of the diaphragm just the same way similar sound waves from the rear mic would reach the back and the front of the diaphragm.
This cardioid polar pattern derives its name from its resemblance to a heart. At the same time, it’s the most common unidirectional polar pattern.
The cardioids microphone is more sensitive to sound that is coming from the front of the mic and at the same time least sensitive to sounds that are coming from the rear of the microphone.
The cardioid microphone has a great ability to be used by two singers at a go. This is possible by the pickup angle of 131 degrees that it is endowed with.
This type of microphone still can pick up a vocalist with the amazing wandering microphone technique with high quality and excellence.
The cardioid pattern has excellent feedback rejection.
A hypecardioid is simply the exaggerated version of the cardioid polar pattern. The principal characteristic that distinguishes hypercardioid is that it eliminates all the sounds from the sides and the rear captures.
It isolates the sound from the direction that has a lot of noise in the surroundings. It has a fantastic ability to pick up the sound of a subject at a distance.
When you keenly analyze hypercardioid patterns, you will realize that they offer much narrower pickups as compared to supercardioids.
Unidirectional patterns are commonly associated with the picking of sound predominantly from one direction. It is crucial to note that this includes cardioids and hypercardioid microphones.
A hypercardioid microphone has an excellent directionality at the front and it is a great choice, especially when making a recording and the sound waves are coming from the front.
The subcardioid polar pattern is also known as wide cardioids. It is a lesser known relative to the popular cardioid pattern. This microphone usually has a polar pattern that is closely similar to the midway point between a cardioid and an omnidirectional pattern.
This subcardioid pattern is usually unidirectional, but it is also essential to note that it can pick sounds from all other directions in a clear way. However, the picked sound has less amplitude.
When you look at it keenly, you will begin to see the subcardioid polar pattern like a cross-generated between a cardioid and omnidirectional pattern.
The reason why the subcardioid pattern is classified as unidirectional is that, it is mostly sensitive in only one direction. Unlike in other popular scenarios with different unidirectional patterns, subcardioid patterns do not have any null points.
Instead of having lobes of sensitivity and null points, the subcardioid polar patterns are simply made with less sensitivity to sound waves originating from the back compared to those originating from the front.
This facilitates to subcardioid microphones sounding relatively realistic and natural as in the case of omnidirectional microphones and at the same time maintaining features that make it unidirectional.
The supercodioid polar pattern is a closer relative of the cardioids polar pattern but often misunderstood. Having a proper understanding of the supercardioid pattern helps you when you are recording in the studio or when having a performance at the stage.
What can we refer a supercordioid microphone to? It is the most sensitive microphone when it comes to the direction the microphone is facing. Usually, it has a very directional pickup pattern, and it has null points at 127 and 223 degrees.
The microphone has lobe of sensitivity at the back of the microphone. This kind of microphones is mostly popular in the film making industry simply because of their high directionality.
To avoid feedback when using this kind of microphones, make sure that you do not point the microphone so that the rear lobes will be aiming to the loudspeaker or the live monitor.
You must note that the supercardioid microphone has null points because of their ideal pattern.
A proper understanding of the different microphone polar patterns is all about understanding the comparisons that exist between them in terms of their properties and application.
Generally speaking, there in no polar pattern that is better than the other. However, different polar patterns are more suitable in different applications than others. You have to be conversant with the different polar patterns and where they are ideally suited.
All the polar patterns discussed above find their applications somewhere. Regardless of their properties, these polar patterns will require the user to find them consistent performance across various frequencies.
This means that an excellent microphone, regardless of its properties and polar pattern, will perform excellently and consistently across the complete frequency spectrum.