## Polar Patterns A key aspect of how a microphone works is its directionality. A microphone does not necessarily pick up sound equally from all sides. This can be understood by examining a microphone's polar patterns.  ### Cardioid Imagine being able to turn around and no longer hearing the person behind you. Wouldn't that be a great way to put an argument out of sight and out of mind? A microphone with a cardioid polar pattern can achieve something similar. Named for its heart-shaped pickup pattern, a cardioid microphone captures your voice with no loss in volume when you are standing in front of it, as indicated by the blue trace on the outer edge of the polar diagram. However, as you move towards the back of the microphone, the blue trace moves inward, showing a decrease in volume (as represented by the pink decibel values). Being a directional microphone, it is also susceptible to the proximity effect. [ ### Supercardioid and Hypercardioid As a microphone becomes more directional, it starts to reject sounds from the sides, as seen in the supercardioid polar pattern below. Notice how the blue outline narrows on the sides. However, a trade-off with more directional microphones, such as supercardioid and hypercardioid microphones, is that they start to pick up sounds from the back as well. Shotgun microphones, which are often supercardioid or hypercardioid, require careful handling by boom operators who must point the boom arm in the correct direction. Since these microphones can pick up sound from behind, boom operators need to remain quiet to avoid being picked up by the microphone themselves.  ### Bidirectional or Figure 8 Bidirectional microphones pick up sounds equally from the front and back due to their Figure 8 polar pattern. These microphones are useful when you have two sound sources on either side that you want to capture equally. Ribbon microphones typically feature a bidirectional polar pattern. As directional microphones, they exhibit a strong proximity effect.  ### Omnidirectional Our ears function much like omnidirectional microphones, capturing sounds from all directions. This means the concept of not being able to hear someone behind us if we turned around doesn't apply to our hearing capabilities. As shown in the graph below, the blue trace on the outer edge of the polar pattern graph indicates that sounds are not attenuated from any specific direction, demonstrating the consistent sensitivity of omnidirectional microphones. Additionally, omnidirectional microphones do not exhibit the proximity effect, maintaining a consistent frequency response regardless of the sound source's distance.  ### Switchable Polar Patterns Some microphones have a switchable polar pattern, allowing you to change the directionality of the microphone depending on the particular recording circumstance. This flexibility makes them versatile tools for a variety of recording environments, enabling you to adapt to different sound sources and acoustics by selecting the most appropriate polar pattern for the situation.  ## Frequencies and Polar Patterns In reality, polar patterns are more complex. Similar to how a microphone's frequency response changes with distance (proximity effect), frequencies can also influence a microphone's polar pattern. The legend on the bottom right shows different frequencies, illustrating how, at higher frequencies, this "omnidirectional" microphone becomes quite directional. Higher frequencies are better captured in front of the microphone.  Similarly, in the graph below, you can see how this cardioid microphone actually becomes quite omnidirectional at lower frequencies. This means it isn't effective at rejecting low frequencies from any specific direction.  ## Microphone Address Generally, the logo on a microphone indicates the front, where you should speak into, known as the microphone’s address. However, it’s not always obvious which direction to speak into, so it’s crucial to read the manual to avoid mistakes. Microphones come in two main types of address: side-address and top-address. Side-address microphones capture sound from the side of the microphone body, while top-address microphones capture sound from the top. For example, the Sennheiser 421 has a metal bar on the top, which might seem confusing, but it is actually designed to be a top-address microphone. This design allows broadcasters to speak into it without their faces being obscured on TV. Correct orientation is essential for proper microphone usage. Polarity only matters if you orient yourself correctly according to the microphone’s address. When in doubt, always refer to the manual to ensure you’re using the microphone correctly. See the diagram below for the difference between side-address and top-address microphones.  ## Curated Resource Watch the video to see and hear how polar patterns affect the signal strength of the microphone depending on your position relative to the microphone. )