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When it comes to choosing a microphone, one of the most important factors to consider is its polar pattern. Microphone polar patterns determine how a microphone captures sound from different directions, making it a crucial element in achieving high-quality audio recordings or broadcasts.
In this article, we will delve into the concept of pickup patterns, explore the three main types, and discuss which polar patterns are best suited for different applications, such as vocals and streaming.
Microphone polar patterns, also known as pickup patterns, describe the microphone’s sensitivity to sound from different angles. It illustrates the microphone’s response to sound waves from various angles relative to its diaphragm.
A microphone’s polar pattern is typically represented graphically, showing its sensitivity in a 360-degree circle around the microphone’s axis.
There are five main polar patterns for microphones. These different polar patterns can determine which microphone will be the best for you. Read further to find the right polar pattern for your content.
Cardioid polar patterns resemble a heart shape when graphically depicted. It is highly sensitive to sound from the front of the microphone and gradually decreases sensitivity to the sides and rear. Cardioid mics are ideal for isolating sound directly in front of them while rejecting unwanted noise from other directions. This makes them a popular choice for vocals and live performances.
The cardioid polar pattern stands as one of the most prevalent configurations found in modern microphones, offering a blend of both omnidirectional and bidirectional microphone characteristics. When graphed on a 360-degree sphere, the fusion of these two patterns forms a distinctive heart-shaped design, hence the term ‘cardio’ derived from this shape.
In the realm of the cardioid polar pattern, its primary sensitivity lies squarely in front of the microphone in what’s referred to as the on-axis position. It exhibits a diminishing sensitivity as one moves towards the microphone’s sides and culminates in a null point at the rear.
As mentioned earlier, a cardioid polar pattern microphone is exceedingly common across various microphone types, encompassing small-diaphragm condensers, large-diaphragm condensers, dynamic microphones, lavalier microphones, and even USB microphones. In most cases, microphones tailored for vocal applications, whether for live performances or studio recordings, opt for a cardioid microphone.
This choice allows for the direct capture of sound positioned directly in front of the microphone while simultaneously mitigating sensitivity to rearward sound and reducing side sensitivity. This distinctive feature effectively eliminates the risk of feedback from other instruments or equipment.
Due to their heightened sensitivity in the on-axis position, accompanied by a null point at the 180-degree angle, A cardioid microphone excels in gain control. In studio environments, these patterns enable the adjustment of gain settings to amplify sound without fear of feedback, making them particularly well-suited for instruments with wide dynamic ranges.
There are several benefits of cardioid mics:
The cardioid mic polar pattern branches into two more polar patterns: Hypercardioid and Supercardioid. These two polar patterns are, of course, variations of the classic cardioid shape, but with a tighter directionality at the front.
The hypercardioid polar pattern closely resembles the supercardioid pattern, characterized by an even narrower scope of on-axis directivity and heightened insensitivity to sounds originating from the sides at 90 and 270 degrees.
Notably, hypercardioid polar patterns null off-axis sounds, occurring at 110 and 250 degrees. It’s essential to recognize that hypercardioid microphones, in contrast to supercardioid ones, exhibit a rear lobe of increased sensitivity at 180 degrees.
When visualized in a sensitivity diagram encompassing the microphone, hypercardioid polar patterns roughly combine elements of bidirectional and omnidirectional polar patterns in a ratio of approximately 3:1. Similar to supercardioid microphones, hypercardioid microphones are frequently employed for specialized purposes, particularly in drum miking setups.
They excel at isolating the desired sound source while minimizing interference from adjacent instruments, thus reducing bleed. It’s worth noting that many large-diaphragm condenser microphones offer a selectable hypercardioid pattern, achieved by employing two pressure-gradient capsules that capture audio from both sides of the diaphragm.
There are several benefits to the hypercardioid polar pattern:
Supercardioid polar patterns represent a refined version of the cardioid pattern, characterized by even more precise directionality. In the supercardioid pattern, on-axis directionality is enhanced, resulting in reduced side sensitivity and lower volume levels at 90 and 270 degrees.
However, this heightened front-facing directivity comes at the cost of increased sensitivity towards the microphone’s rear, notably at 180 degrees. In essence, the supercardioid pattern combines elements of omni and bidirectional patterns in a ratio of approximately 5:3. The presence of a rear lobe in the polar pattern at 180 degrees sets supercardioid mics apart from cardioid counterparts.
Consequently, supercardioid polar patterns capture a minor amount of sound from the rear of the microphone. This aspect is particularly relevant when using multiple microphones in a studio environment, such as when miking large sounds like a drum kit. Typically, supercardioid microphone polar patterns are found on microphones specifically designed for drums or vocal recordings, effectively isolating the primary sound source from external noise and ambiance.
This isolation results in a focused tone, while concurrently rejecting bleed from neighboring instruments. However, it’s essential to note that due to their pronounced directivity, supercardioid microphone polar patterns may be vulnerable to vocal plosives and the proximity effect. The latter phenomenon causes ‘b’ and ‘p’ sounds to become more pronounced and louder as the microphone approaches the sound origin.
Supercardioid mics boast the following benefits:
An omnidirectional polar pattern, often abbreviated as omni, boasts a unique sensitivity profile, picking up sound with equal responsiveness from any distance factor. This describes how far away a directional microphone can be placed in comparison to an omnidirectional microphone while preserving the same ratio of direct and reflected sound.
This results in uniform sound capture spanning a complete 360-degree sphere, making it both conceptually straightforward and graphically easy to depict.
This distinctive characteristic of omnidirectional patterns means that there is no requirement to orient the microphone’s front toward the sound source. In theory, the microphone maintains consistent gain levels even when placed at an angle relative to the sound source. An omni pattern provides the best bass response and flattest frequency response, and is the least sensitive to handling or wind noise in comparison to all other polar patterns.
An omnidirectional polar pattern is commonly employed in clip-on lavalier and headset microphones for on-stage performers. This choice ensures that, regardless of head movement away from the microphone, the volume level remains constant, yielding a uniform sound. However, omni patterns are not limited to these microphone types and can also be found in large diaphragm condenser microphones equipped with pattern-switching capabilities.
In a studio setting, utilizing an omni pickup pattern proves highly functional, as it avoids proximity effects, eliminating issues such as pronounced ‘p’ or ‘b’ sounds, resulting in smoother recordings.
It’s worth noting that the 360-degree sensitivity of multi-pattern microphones means that they capture everything in close proximity to the sound source. This can encompass unwanted noises like background AC fan systems or mechanical computer sounds.
An omni polar pattern offers a lot of benefits:
A figure-of-8 microphone, often referred to as bidirectional, possesses the unique ability to capture sound with equal sensitivity from both the front and back of the microphone, while effectively rejecting sounds arriving from the sides. These microphones employ a ‘pressure-gradient’ capsule design, responding to variations in air pressure between the front and back of the microphone.
The figure-8 pattern has the same sensitivity at 0° and 180°, consequently, sound originating from lateral angles, specifically at 90 degrees and 270 degrees relative to the front, exerts equal pressure on both sides, resulting in cancellation or nullification of these sounds, effectively rejecting them.
The Figure 8 polar pattern is most commonly encountered in ribbon microphones, owing to their utilization of the ‘pressure-gradient’ capsule design, which exposes both sides of the microphone to sound pressure. Figure-of-8 polar patterns prove highly advantageous in studio recording scenarios.
When two Figure 8 polar pattern microphones are paired, they can be harnessed for stereo recording techniques, such as Mid/Side recording and Blumlein recording. In the context of the Mid/Side recording technique, a more symmetrical distribution of sound pressure is observed, creating a ‘true bidirectional’ polar pattern where both sides of the microphone capture audio with more evenness.
Several benefits of a bidirectional polar pattern microphone include:
When it comes to capturing sound accurately and achieving professional audio quality, selecting the right polar pattern for your microphone is crucial. Polar patterns determine how a microphone captures sound from different directions, and each pattern has its own strengths and weaknesses. Your microphone’s polar pattern will determine its use for your content.
The best polar pattern for vocals depends on the specific recording environment and your desired sound. Here are some considerations to help you make the right choice:
Selecting the best polar pattern for your streaming microphone depends on several factors: