A headphone microphone’s ability to deliver clear voice calls depends largely on how it picks up sound. The directionality, or pickup pattern, determines which sounds the microphone captures and which it rejects. Understanding these patterns can help you choose a headset that performs well in noisy environments, whether you’re on a call in a busy office or walking down a city street.
Understanding Microphone Pickup Patterns
Every microphone has a directionality characteristic that describes its sensitivity to sound relative to the angle from which the sound arrives. Shure’s guide to microphone directionality explains that this is plotted on a polar pattern graph, which shows the variation in sensitivity 360 degrees around the microphone, with the front at 0 degrees. The three basic directional types are omnidirectional, unidirectional, and bidirectional.
Omnidirectional
Omnidirectional microphones are equally sensitive to sound arriving from all angles. According to Shure, they do not need to be pointed in any particular direction to capture the source sound. This can be useful in some situations, but not in others. Omni mics tend to sound particularly open and natural compared to unidirectional or bidirectional alternatives, making them a good choice in studio environments with good acoustics or live applications where stage volume is low. The trade-off is a lack of directionality: if you need to reject background noise, room ambience, or monitor feedback, an omnidirectional microphone is not a suitable selection.
Unidirectional
Unidirectional microphones are most sensitive to sound arriving from directly in front and less sensitive in other directions. Shure notes that this makes them effective at isolating the desired on-axis sound from unwanted off-axis sound and ambient noise. Within the unidirectional category, there are three main polar patterns: cardioid, supercardioid, and hypercardioid.
Cardioid. Cardioid is the most commonly used directional polar pattern. Shure describes it as having a wide on-axis pickup area and maximum rejection at 180 degrees off-axis, which results in high gain before feedback when stage monitors are placed directly behind. In many cases, ambient noise is reduced by approximately two-thirds when compared to an omnidirectional counterpart, making cardioid a staple for live performance and touring.
Supercardioid and hypercardioid. Both supercardioid and hypercardioid options offer narrower front pickup angles than cardioid. Shure states that the supercardioid has a front pickup angle of 115 degrees, while the hypercardioid has 105 degrees, alongside greater rejection of ambient sound. The supercardioid is least sensitive at 125 degrees off-axis, and the hypercardioid at 110 degrees. When placed properly, they can provide more focused pickup than a cardioid pattern with better rejection of ambient noise and feedback. However, Shure cautions that hypercardioids are significantly more sensitive to sound from behind than supercardioids, so careful microphone placement is especially important. Singers who move the microphone while performing will find that even small movements on a hypercardioid affect performance more than on a cardioid or supercardioid.
Shure also points out several factors to consider with unidirectional microphones. The proximity effect causes bass response to increase as the microphone is moved closer to the sound source. Off-axis coloration means the microphone’s frequency response may not be uniform at all angles, with high frequencies typically most affected. Because directional microphones pick up less ambient sound than omnidirectional types, they can be used at somewhat greater distances from a sound source and still achieve the same balance between direct sound and background sound. Hypercardioid microphones can be placed slightly further away than a regular cardioid and still obtain the same ratio of direct to reflected sound.
Bidirectional (Figure-of-Eight)
Bidirectional microphones have two angles of maximum sensitivity and two angles of minimum sensitivity. Shure explains that they produce a very open and natural sound, similar to omnidirectional microphones. The coverage or pickup angle is about 90 degrees at both the front and the rear, and they have the same amount of ambient pickup as a cardioid. This pattern can be used for picking up two opposing sound sources, such as a vocal duet. All ribbon microphones are naturally figure-of-eight.
How Pickup Patterns Affect Call Quality
When a headphone microphone is used for voice calls, the pickup pattern directly influences how well your voice is isolated from the surrounding environment. A unidirectional pattern, particularly cardioid or supercardioid, is often preferred because it focuses on the sound coming from your mouth while rejecting noise from the sides and rear. This can make a noticeable difference in a noisy office or on a busy street. The proximity effect can also add warmth to your voice when the microphone is positioned close to your mouth, though too much bass boost may make speech sound boomy. If you frequently take calls in quieter spaces, an omnidirectional microphone might capture a more natural tone, but it will also pick up more room echo and background sounds.
Polar pattern consistency across frequencies also matters. Shure notes that a great quality microphone maintains a consistent polar pattern across the entire frequency spectrum. Cheaper microphones may show a supercardioid pattern at some frequencies but behave closer to omnidirectional at others, making it harder to achieve reliable noise rejection. When evaluating a headset for calls, it helps to understand the general pickup pattern, but actual performance will vary by design and implementation. For more on interpreting specifications, see our guide on how to read headphone specs.
Active Noise Cancellation and Transparency for Calls
Many modern headphones and earphones include active noise cancellation (ANC) and transparency modes that also involve the built-in microphones. Apple’s support page explains that with Active Noise Cancellation, an outward-facing microphone or microphones detect external sounds, which the device then counters with anti-noise, canceling the external sounds before you hear them. An inward-facing microphone listens inside your ear for unwanted internal sounds, which are also countered with anti-noise. Transparency mode lets outside sound in, so you can hear what is going on around you.
These features can improve call quality in different ways. ANC reduces background noise for you, making it easier to hear the other person. Transparency mode can be useful when you need to stay aware of your surroundings during a call, such as when walking near traffic or waiting for an announcement. Apple notes that Active Noise Cancellation and Transparency mode work best when the earphones fit well, and that Adaptive Audio can adjust noise cancellation automatically based on your surroundings. For a deeper look at these technologies, visit our articles on active noise cancellation and transparency mode.
Quick Checks for Better Call Audio
While the microphone’s pickup pattern and the headphone’s noise-control features play a big role, a few simple checks can help you get the most out of your headphone microphone during calls.
- Position the microphone as directed. Follow the manual for where a boom or inline mic should sit; Shure notes that bass rises as a directional mic moves closer to the source.
- Ensure a good fit. For in-ear models, a secure seal helps the inward-facing microphone work effectively and improves noise isolation. Follow the manufacturer’s fit guide for your specific model.
- Use the right listening mode. Switch between ANC and transparency depending on your environment.
- Check your settings. Many devices let you customize which noise-control modes are available and how the microphone behaves. Consult your product manual for steps, as they differ by model.
- Keep microphones clean. Follow the manufacturer’s cleaning instructions for mesh and openings.
For a broader look at how microphone specs fit into the bigger picture, see our headphone specifications section.
Frequently asked questions
Which pickup pattern is best for phone calls?
A unidirectional pattern, especially cardioid, is commonly used for calls because it focuses on the speaker’s voice and reduces background noise from other directions. The exact performance depends on the headset design and how the microphone is positioned.
Does active noise cancellation improve microphone quality?
Apple describes ANC as reducing the outside sound you hear. How clearly the other person hears you depends on the microphone’s pickup pattern and the headset’s design.
Can I use transparency mode during a call?
Yes. Transparency mode lets outside sound in, so you can stay aware of your surroundings while talking. This can be helpful in situations where you need to hear announcements or traffic.
For more on headphone microphones, visit our Microphones category page.
