How to Fix “Pop” Goes the Vocal

Pops come from speech elements called plosives — and if you think they have something in common with the word “explosion,” you’re right. Pops happen when the burst of air generated by your lips separating with a force of air behind them hits the microphone capsule. When these bursts associated with letters like “p” and “b” hit your poor mic’s diaphragm with the force of a 60-mph gust of wind, it creates a huge amount of low-frequency energy, which can mar a vocal and sound horrible. Let’s find out how to prevent this, or at the very least repair it if it does happen to you.
The Primary Fix: Get It Right at the Source
The best strategy is to not record pops in the first place, so here are several tips on nuking pops at the source.
Enable the low-frequency roll-off switch on the mic or preamp
This type of switch, also called a low-cut or a highpass (fig. 1), reduces the mic’s sensitivity to pops. Although it won’t get rid of pops altogether, it can attenuate them by filtering out low-frequency content.

Figure 1: AKG’s C414 mic has a 4-position low-cut switch — off, 40Hz, 80Hz, and 160Hz. You’d use either the 80Hz or 160Hz setting for most vocals.

Learn not to sing plosive sounds so forcefully
This requires self-control when doing vocals (which, unfortunately, is when you don’t want to be thinking about self-control — just singing from the heart). Nonetheless, with practice, it’s possible. Don’t purse your lips or build up air in your mouth; let the “p” and “b” sounds slide out of your mouth instead of burst out. Even turning your head slightly to the side when singing plosives can reduce them considerably. Once you nail this technique, you’ll be surprised at how easy it is to tame pops.
Use an omnidirectional mic
A nondirectional mic won’t cure pops per se, but it doesn’t exhibit the proximity effect of a directional mic, which accents the bass. Although cardioid mics are pretty much essential for live performance to reject off-axis sounds, the pattern response is less of an issue for solo vocals in the studio.
Position yourself the correct distance from the mic
A good rule of thumb is to stretch your thumb and little finger as far apart as possible (about 7–10 inches) and use that to measure the distance from the mic to your mouth. Also aim very slightly off-axis, like just below the mic’s diaphragm.
Use a properly positioned pop filter
There are multiple kinds of pop filters at various price points, but frequently the add-on pop filters will perform better for heavy plosives than the ones that come as accessories. Sweetwater offers a large collection of pop filters, so refer to that for more options. Subjective bias alert: I generally prefer metal mesh over nylon, especially for live use, because of the durability factor. Blue’s The Pop (fig. 2) is a good example of a pop filter with a metal mesh screen.

Figure 2: Blue’s The Pop has a fine metal screen, but also a widely spaced wire mesh (so it doesn’t affect the sound) that provides additional protection.

Another popular screen, Stedman’s Proscreen XL (fig. 3), is a good example of how different pop screens fulfill different needs. This one is a good choice for studios with a lot of vocalist traffic, because the screen is made out of a proprietary material that’s easy to clean.

Figure 3: Interestingly, the Stedman screen is not “bidirectional” — the mesh diverts air downward, so you need to sing into the logo side.

As to placement, it’s a misconception that you want to place the screen as close to the mic as possible. Pop screens don’t stop blasts, but simply divert them. To find a pop screen’s “sweet spot” that provides significant air blast reduction without being too far away from the mic, place the palm of your hand an inch behind the pop screen, and blow into the front. Move your hand further away from, or closer to, the screen to find the best combination of proximity to the rear of the screen with minimum air currents — that’s the distance to place the pop screen in front of the mic.
The Secondary Fix: Fix It in the Mix
Sometimes, despite your best efforts, pops will creep into your recordings. There are three main ways to get rid of these after the fact.
Sharp highpass filter
If the pops aren’t too severe, you may be able to save time and effort by inserting a very steep highpass filter on the vocal track. My go-to for this is the Waves LinEQ, but you can also create a “virtual pop filter” with multiple stages of EQ (fig. 4) to create a super-steep highpass filter that nukes the low frequencies.

Figure 4: Studio One’s Pro EQ is using a low-cut filter (with a 48dB/octave slope), a low-shelf filter, and our bands of parametric EQ to create a virtual pop filter.

Fade in on the pop
The worst part of the pop occurs at the beginning of a plosive, but the sound still persists somewhat after the pop. Split the vocal clip just before the plosive. (You’ll learn to recognize plosives; they’re low frequency and thus longer waveforms.) Then fade in over the pop’s beginning (fig. 5).

Figure 5: Splitting a clip just before the pop and creating a fade-in not only gets rid of the pop but also gives you a lot of leeway regarding how much you want to remove.

The fade lets you control how much of the pop you want to keep. You can also tailor the amount very precisely by changing the fade curve (linear, concave, or convex), and if necessary, splitting partway through the plosive to avoid the worst part entirely, then fading in from there. Although time-consuming, this is my preferred way to remove after-the-fact pops.
Sharp highpass filter on only the pop
When all else fails, this option works for really severe pops. Sometimes adding a highpass filter to remove serious pops from a track thins out the vocal’s low end too much, but you can’t do a fade without leaving in an objectionable amount of low end. Applying a steep highpass filter to only the pop (fig. 6) lets you really slash the low frequencies, without affecting the rest of the vocal.

Figure 6: The Waves LinEQ is demolishing the low frequencies by processing only the pop. The section outlined in red shows Studio One’s option for processing only a particular event, also called a clip.

The section outlined in yellow shows the original clip with the pop (bottom) and the clip after trimming all the lows (top). If needed, you can also fade in over the processed clip to eliminate any vestiges of pop.
Ducking
Fading in works if the plosive is at the beginning of a word, but if the pop is in the middle, you have two options. As mentioned previously, you can apply a highpass filter on only the pop; this works well if removing the pop doesn’t affect the voice’s timbre negatively. Another option is to split the plosive into its own clip, and then pull down the gain on just that region, as shown in figure 7 (or automate a gain change). 

Figure 7: Separating a pop in the middle of a word, then reducing the level, can reduce mid-word pops.

However, there are two issues with ducking. First, if separated into its own clip, there can be an abrupt level change going into or out of the region, which requires adding a crossfade. Some programs do this automatically, and even let you specify an automatic crossfade time. With automation, if you program a short fade-in and fade-out, you won’t have level-change issues. Second, if the pop consists of annoying low-frequency energy, then you just have lower-level annoying low-frequency energy. To solve this, you can “double down” on the pop — combine a moderate amount of highpass filtering with a moderate amount of gain reduction. It requires some effort to get both settings just right, but most of the time, this kind of drastic repair won’t be necessary — and definitely won’t be necessary if you got the sound right at the source!

If you need a pop filter or a software solution for fixing plosives, call your Sweetwater Sales Engineer at (800) 222-4700.

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