You may be the most talented voice actor in the world, but it won’t count for much unless you have the right equipment! Sound recording is a tricky business and there are a few key components that you need to know about. One of them is the pop filter, which is our topic today. Read on to learn about what pop filters are and how you can use them as a voice actor.
Pop filters eliminate the popping noises (hence the name) that can occur when you talk into a microphone, most commonly caused by “plosives.” These are bursts of air pressure that you push out whenever you pronounce certain consonant sounds. In English, plosives typically result when you say words with the letters p, k, b, t, g, and d. These noises are an issue because they can overwhelm your microphone’s input in small bursts, resulting in clipping in your recording—the distortion you hear when a sound signal is overwhelmed.
As an added bonus, pop filters also shield your microphone from damaging particles (mainly your saliva).
What are pop filters made out of?
Pop filters for microphones are composed of attenuating (or sound-energy-reducing) material, held together in a frame of hard plastic or metal, resulting in a flat or curved porous barrier that can be mounted between your mouth and your microphone. Layers of woven nylon comprise the most commonly used filters; they’re great for breaking up the sound that you project while speaking, keeping that popping effect to a minimum.
You can also find pop filters made with mesh metal screens that redirect your breath rather than let it pass through. The results are comparable, but metal pop filters are generally more expensive (they also tend to be more durable).
How to use a pop filter
Pop filters are placed between a voice actor and their microphone, either on a stand or attached to the microphone itself via a mount. You’ll want to position it further away from your microphone if you’re really belting out your lines. As we mentioned before, pop filters can either be flat or curve outwards. With curved ones you have more room to maneuver while recording, while you’ll have to direct your vocals into the center of flat ones.
The further away your pop filter is from the condenser (the bit that picks up sound), the less any popping will come through. But if you’re recording at a lower decibel level, keep your pop filter closer to the mic. Note that your pop filter might dull the sound slightly, depending on your vocal range. Pay attention to your levels and listen back to your recordings to see what works best for you!
What’s the difference between a foam cover and a pop filter?
If you’re not sure whether to use a foam cover vs. a pop filter, ask yourself a simple question: where are you recording?
Pop filters are ideal for indoor studios where you don’t have to worry about the elements. When you need to take wind and other outside noises into consideration, then you should shield your microphone with a foam cover (a.k.a. a foam windscreen). Not only will this snug foam jacket reduce ambient noise, but it’ll also protect your mic capsule.
Pop filters and foam covers have distinct uses, so you may want to invest in both. If you’re using a particularly sensitive mic, attaching both a pop filter and foam cover at the same time can do the trick of eliminating unwanted sounds across the board.
These simple tools have a niche-but-valuable role in sound recording. Are pop filters necessary? “A pop filter is needed if plosives are a problem,” says voice actor and podcast producer Jamie Muffett. “That sounds obvious, but not all situations require one.”
For example, your choice of microphone matters. “A pop filter is diffusing that blast of air that interacts with the diaphragm of the microphone,” says Muffett. “If, however, you have a microphone that isn’t as sensitive to pops, or its design prevents them from interacting with the diaphragm, such as the Shure SM7b, a pop shield isn’t needed.”
Another consideration is where you position your equipment. “Good mic placement and mic technique can reduce or eliminate the need for a pop filter,” says Muffett. “For example, rather than speaking or singing directly down the barrel of the mic, speaking across it at 45 degrees means the air will shoot past the front of the microphone, and not interact with the diaphragm at all.”
If plosives are posing a problem (try reading that phrase into a microphone!) and you don’t have a pop filter handy, there are DIY alternatives. “Place a finger or a pen or pencil in front of the mouth, similar to how someone may gesture for silence. This diverts the airflow either side of the finger or pencil, and thus either side of the microphone,” suggests Muffett. This technique, however, has distracting drawbacks, as “the person utilizing this technique has to be hyper aware of when this should be applied,” Muffett notes, “and is another thing to think about during a performance.”
Can you make your own pop filter?
If your budget is extremely tight or if you’re strapped for time, you can always DIY a pop filter out of a wire coat hanger and nylon stockings. Just pull the bar of the hanger out, stretch the stocking over it, and presto! Instant pop filter. If you're really desperate, you can even put a sock over your microphone. It’ll prevent popping from getting through, but it’s important to note that it is likely to muffle your vocals as well.
Luckily, pop filters are on the cheaper end of the spectrum of audio recording equipment. While high-end pop filters can cost upwards of $100, you can find a starter for under $10.