Some mics pick up sound from all directions in an almost equal measure, while others can only focus on one direction, so how do you know which is best?
The difference between these mics is their polar pattern. An omnidirectional microphone picks up sound from all directions equally, useful for recording rooms. A directional mic only picks up the sound from the one direction it’s directed towards and cancels out most background noise, useful for loud venues.
In this article, I’ll discuss the differences between these types of mics and when to use each so you don’t pick the wrong one.
Since it can pick up sound from many directions at once, the omnidirectional mic is used for studio recordings, room recordings, work meetings, streaming, gaming, and wide sound source recordings such as musical ensembles and choirs.
On the other hand, a directional mic picks up sound from one direction only, so it’s ideal for recording in a noisy venue where the mic is pointed towards the main sound source (the performer).
Polar pattern
Before we compare the two types of mics, it’s important to understand the concept of microphone directionality, also called polar pattern.
This concept refers to the direction (s) from which your microphone picks up the sound. Sometimes more sound comes from the rear of the mic, sometimes more from the front, but in some cases, the sound comes from all directions.
Therefore, the main difference between an omnidirectional and a directional mic is the polar pattern, which refers to how sensitive a mic is to the sounds coming from different angles.
Thus, this polar pattern determines how much signal the mic picks up from a certain angle.
Omnidirectional Mic
As I mentioned at the beginning of this article, the main difference between the two types of microphones is their polar pattern.
This polar pattern is a 3D space around the most sensitive area of the capsule.
Originally, the omnidirectional mic was known as a pressure mic because the mic’s diaphragm measured the sound pressure at one point in space.
The basic principle behind an omnidirectional mic is that it’s supposed to pick up the sound equally from all directions. Thus, this mic is sensitive to sounds coming from all directions.
In short, an omnidirectional mic picks up the incoming sound from all directions or angles: front, sides, and rear. However, if the frequency is high, the mic tends to pick up sound directionally.
The omnidirectional mic’s pattern picks up the sounds in proximity to the source, which provides plentiful GBF (gain-before-feedback).
Some of the best omni mics include the Malenoo Conference Mic, which is ideal for working from home, hosting zoom conferences and meetings, and even gaming since it has a USB connection.
You can also use the affordable Ankuka USB Conference Microphone, which is great for meetings, gaming, and recording your voice.
Directional Mic
A directional mic, on the other hand, does NOT pick up the sound from all directions. It only picks up sound from one specific direction.
These mics are designed to minimize and cancel out most of the background noise. A directional mic picks up the most sound from the front.
As I mentioned before, directional mics are best for recording live sounds in noisy venues where you only want to pick up sound from ONE direction: your voice and instrument.
But thankfully, these versatile mics are not just limited to noisy venues. If you use professional directional mics, you can use them farther from the source (i.e., podium and choir mics).
Directional mics also come in smaller sizes. The USB versions are commonly used with PCs, laptops, and smartphones because they minimize background noise. They are great for streaming and podcasting too.
There are three main types of directional or unidirectional mics, and their names refer to their polar pattern:
- cardioid
- supercardioid
- hypercardioid
These microphones are sensitive to external noises, such as handling or wind noise.
A cardioid mic is different from an omnidirectional because it rejects much of the ambient noise and has a wide front-lobe, giving the user certain flexibility as to where the mic can be placed.
A hypercardioid rejects almost all the ambient noise around it, but it has a narrower front-lobe.
Some of the best directional mics brands include ones for gaming like the Blue Yeti streaming & gaming mic or the Deity V-Mic D3, which is ideal for use with smartphones, tablets, and laptops.
Use it to record podcasts, audio snippets, vlog, sing, and stream.
When to use directional & omnidirectional mic
Both these types of mics are used for different purposes. It all depends on what type of sound you want to record (i.e., singing, choir, podcast) and the space you’re using your mic in.
Omnidirectional mic
You don’t need to point this type of mic in a particular direction or angle. Thus, you can capture sound from all around, which may or may not be useful depending on what you need to record.
The best use for omnidirectional mics is a studio recording, recording in a room, capturing a choir, and other wide sound sources.
An advantage of this mic is that it sounds open and natural. They are also a great choice to use in a studio environment where the stage volume is pretty low, and there are good acoustics and live applications.
Omnidirectional is also the best choice for mics that are close to the source, such as earsets and headsets.
Therefore you can also use them for streaming, gaming, and conferences, but the sound might be less clear than a hypercardioid mic, for example.
This mic’s disadvantage is that it can’t cancel out or minimize background noise due to its lack of directionality.
So, if you need to minimize ambient room noise or monitor feedback on-stage, and a good mic windscreen or pop filter won’t cut it, you’re better off with a directional mic.
Directional mic
This type of mic is effective at isolating the on-axis sound you want from one specific direction.
Use this type of mic when recording live sound, especially live musical performances. Even on a sound stage with high noise levels, a directional mic, like a hypercardioid, can work well.
Since you point it towards yourself, the audience can hear you loud and clear.
Alternatively, you can also use it to record in a studio with a poor acoustic environment because it will pick up sound in the direction you’re using it while minimizing distracting ambient sounds.
When you are at home, you can use them to record podcasts, online conferences, or gaming. They are also suitable for podcasting and recording educational content.
A directional mic is handy for working and streaming because your voice is the main sound your audience hears, not the distracting background noises in the room.
Also read: Separate Microphone vs Using a Headset | Pros and Cons Of Each.
Omnidirectional vs. directional: the bottom line
When you set up your mic, always consider the polar pattern and choose the pattern that most suits the sound you want.
Each situation is different, but don’t forget the general rule: use the omni mic for recording in the studio and home use such as work-from-home meetings, streaming, podcasting, and gaming.
For live venue musical events, use a directional mic because a cardioid one, for example, will minimize audio behind it, which gives a clearer sound.
Read next: Microphone vs. Line In | The Difference Between Mic Level and Line Level Explained.
I'm Joost Nusselder, the founder of Neaera and a content marketer, dad, and love trying out new equipment with guitar at the heart of my passion, and together with my team, I've been creating in-depth blog articles since 2020 to help loyal readers with recording and guitar tips.