Hiss, crackle, and pop! It’s not a weird breakfast cereal, but rather the sound of your latest voice over. Pop filters, screens, and shields might be the ideal tools for getting better quality audio. What’s more, they can help you do so without upgrading to a completely new studio space.
Pop filters are simple mesh or screen devices designed to eliminate certain types of audible noise. Although they don’t filter out everything unwanted, they’re essential for dealing with heavy exhalations and plosive sounds.
How do pop filters work, and are they as simple as throwing an old — hopefully clean — sock over your mic? Here’s how to use a pop filter and when you ought to make the effort.
This post has been updated in August 2021.
What Is a Pop Filter?
Pop filters are sections of light cloth or metallic mesh that eliminate popping sounds from your speech. They typically come in the form of circular screens that clip onto mic stands or microphone bodies themselves. Their flexible arms and minimal weight make them convenient in a wide range of studio setups.
How Do Pop Filters Work?
Pop filters are great examples of basic physics in action, and not the difficult kind that takes a doctorate to understand. These open screens and meshes simply interfere with the blasts of air that come from your mouth, forcing them to disperse.
Why is this a good thing? Imagine that you were trying to hang your laundry up to dry in a high-wind area. If you were clever, you might move your clothesline to a spot behind some trees or bushes that would break up the gusts so that you could avoid chasing your underwear down the street.
Pop filters function in a similar way. By standing between the voiceover artist and the microphone, they cause strong puffs of air to break up into turbulent, random wisps. Although they’re not substantial enough to absorb the whole of that energy, they keep it from hitting the mic all at once.
What Do Pop Filters Help With?
Pop filters aren’t some magical answer to managing all kinds of unwanted sound. For instance, they won’t eliminate a low-pitched 60Hz hum caused by a bad power supply. They also can’t help with noise sources like vibrations or radiofrequency interference — for those, you’ll usually need shock mounts, good cables, and experienced voiceover artists.
Pop filters do, however, make a major difference in the way your voiceovers sound. Here’s a quick and easy experiment to prove why. Hold your hand just in front of your mouth, and read the following sentence aloud:
“Here are some sounds that pop pretty badly.”
If you pay close attention to how the air feels hitting your hand, you’ll notice that the last half of that phrase packs a bit more of a punch than the first does. In particular, the last three words feature sudden gusts of air that distinguish them from the softer, preceding sounds. These noises, called plosives or stop consonants, come with significant changes in outward air pressure. Since you create them by temporarily preventing the air from flowing out of your mouth before releasing it, they’re more noticeable than other sounds, like nice, lazy vowels.
In the English language, there are six plosive sounds — /p/, /b/, /k/, /g/, /t/, and /d/. Similar noises occur in other languages, which may also include additional stop consonants. As you can see in this helpful diagram from the folks at The Sound of English, all six of these noises involve some form of airflow blockage.
Plosives release exhaled air in a miniature explosion, which is fitting considering the similarity in names. While they’re usually not forceful enough to be that noteworthy — unless you’re a close-talker — they sound significantly louder in recorded audio.
Plosives produce a rush of air that hits the microphone directly. As such, they can overwhelm the rest of your content with loud, bassy tones. In other words, unfiltered plosives make it extremely hard for listeners to focus on the message.
Another cool aspect of using a pop filter is that it can keep your microphones much cleaner. After paying loads for high-quality hardware, it’d be a shame to ruin it with dust, debris, and whatever else happens to come flying out of your mouth during your next studio session. If you’re using a highly delicate mic, then adding protection is just a smart investment.
Are Pop Filters Absolutely Necessary for Good Sound?
You might get away with not using a pop filter if you pay close attention to how you arrange your studio. For instance, standing off to the side instead of directly in front of a microphone can reduce the amount of high-pressure noise that hits the recording element. In most cases, adding a cheap filter is usually less work than rearranging your space.
Rethinking Your Recording Practices
Working with better-trained voice talent might also help. Veterans are more likely to know about plosives and other forceful sounds. Some can even compensate by adjusting their speech on the fly. What’s more, experienced voice actors tend to be more familiar with typical studio setups and thus less prone to shouting out their p’s, t’s, and b’s. Experts also usually understand that they shouldn’t stand too close to the mic.
Some of the sentences in your voiceover scripts might also benefit from rewrites. For instance, if you have a lot of plosive sounds grouped together, then spreading them out could improve your odds of obtaining clean audio.
Certain microphones may suffer from more plosive pickup than others. For instance, dynamic stage microphones, which use electromagnetic fields to translate sound pressure levels into voltage signals, are often hefty enough to take on explosive sounds without getting overwhelmed. Unfortunately, for most studio work, capacitor mics are the standard, and they love to pop and hiss.
Make Sure It’s Really a Pop Filter — Not a Windscreen
Some microphones also include their own pop filters. One thing to remember is that the mesh on the outside of most mics doesn’t count. On top of being too close to the pickup element to accomplish much, these features are usually geared towards limiting other forms of noise, such as the windscreens that reduce — you guessed it — wind.
Are Some Pop Filters Better Than others?
Some professional-grade pop filters include multiple layers of screen. This arrangement increases the amount of dissipation that occurs when the air from your voice hits the filter — reducing the noise further. The idea is that any unwanted sounds that get past the first layer will dissipate upon reaching the second or third. Whether you’ll notice the difference, however, might depend on how sensitive your ears and recording hardware are.
Pop filters are meant to cut out certain sounds while letting the remainder pass unhindered. As with many things, however, they don’t do this job perfectly. Some engineers and audio purists may feel that certain tightly woven nylon pop filters cause too much interference around the high-end frequencies. The usual solution to this problem lies in switching to a metal pop filter that has a broader mesh spacing.
Even though they don’t involve any rocket science, pop filters need to be well-made. Look for these sure-fire hallmarks of a good anti-plosive recording attachment:
- The pop screens should be stretched tightly across their frames. If they billow around like a ship’s sails, they’ll only add to the unwanted noise.
- The mounting hardware should attach to your mic stand, shock mount, or arm securely without rattling.
- The filter’s diameter should be sufficiently large to block your voiceover artist’s exhalations even if they’re not perfectly on-center.
- The mounting neck should be long enough to leave a gap of about 5 cm (2 in.) between the filter and the microphone. On the other hand, you don’t want to have to keep adjusting or moving the screen out of your way, so pick a nice middle ground by measuring your setup first. Also, read some user reviews to be sure that the gooseneck arm is sturdy enough to outlast repeated adjustments. Some cheaper filters tend to skimp on this component.
- Pop screens that attach directly to microphones might not fit all forms of hardware. Again, always measure your mic before you buy the extras.
How Can I Make a Pop Filter?
So you’ve decided that you’d rather not spend a few dozen bucks on a filter, particularly after emptying your wallet for that fancy audio gear. We hear you, and we’re here to help.
You can make a pop filter pretty quickly using a nylon pantyhose or a similarly light, stretchy fabric. You’ll also want a large, sturdy ring. You can make one with an embroidery hoop, a length of coat hanger wire, or even plain cardboard.
Ready for the super-secret DIY technique handed down through generations of broke recording artists? Affix the fabric to the ring however you can — such as with binder clips, glue, clamps or light wire. Attach your new filter to a stable mounting point. It should sit between your mouth and the business end of the microphone without rattling around.
That’s it, so go out and record something great! Or, check out a few more ideas on how to get started with the DIY approach:
Stop Popping — Put Plosives in Their Place
Pop filters make sung and spoken vocal recordings feel more natural and listenable. Along with shock mounts, shielded cabling, and comfortable ergonomics, they’re integral to modern studio setups.
About to spend your last production-budget dime on a ton of expensive soundproofing? Dreading the idea of editing all of the p’s and t’s out of your script? Look into whether a simple pop filter might make your life easier. Or, talk to a voice over expert about hitting the ideal production stride — and sound.
Ready to start your own voice acting career, get started today with Bunny Studio!