As an audio engineer, you'll no doubt come across clicks and pops at some point in your mixing journey. We also know that these little anomalies can be wildly frustrating, whether you're mixing music, producing a podcast, or editing a video.

However, if you don't take the time to eliminate them, you can take away from your listener's experience.

Luckily, you've come to the right place, as we're going to explore where these clicks and pops originate from so you can learn how to prevent them and get rid of them if they're already plaguing your audio files.

What Are Clicks and Pops?

I like to think of clicks and pops in audio recordings as any abrupt, non-musical, unwanted noise that disrupts the smooth flow of sound.

The question is, where do they come from?

Well, it's difficult to say, as they can be traced back to a variety of causes, whether in your digital or hardware setup.

In the digital world, clicks often arise from errors in data transmission or conversion processes, such as sample rate mismatches or corrupted files. Your computer might experience a brief loss of information and spit out sudden spikes or drops in the audio signal. Poor digital editing is a major culprit in this regard. If you don't properly cut or join your audio clips with fades, you can break the continuity of the waveform.

On the analog or hardware side , clicks and pops can come from several places.

If you're working with vinyl records, for examples, they might be the result of dust particles, scratches, or static electricity impacting the surface of your record.

On the other hand, if your setup has damaged or loose cables, or any out-of-date hardware, it can introduce these sounds into playback.

Knowing where your clicks and pops are coming from is the first step to remedying them. The best way is to consider the variables above and systematically isolate them one by one until you don't hear them anymore. Then you know you've found your culprit.

How To Prevent Clicks and Pops in the First Place

There are several ways to mitigate clicks and pops during the recording process.

For starters, you want to make sure all of your recording equipment is properly connected and that cables are in good condition. I can't tell you the amount of times I've had a weird noise issue in my system, only to realize that it was some old, faulty cable.

Regularly check your cables and make sure they aren't worn out.

In the same vein, make sure you aren't using cheap cables with poor shielding. That five-dollar knock-off Mogami cable you bought won't cut it for long.

If you're recording with microphones, use pop filters and shock mounts to isolate them from mechanical vibrations and plosives, which might otherwise result in clicks and pops in the audio recording.

Keep Your Equipment Clean

If you're recording from vinyl or other analog sources, make sure your media and the playback equipment is clean. Equipment can get dusty fast, and small components, such as turntables and stylus needles, are often the first victims. By keeping your equipment clean, you can drastically decrease surface noise, including clicks and pops.

Know Your Environment

Environmental factors can play a significant role in preventing unwanted noise as well.

In the best-case scenario, you can record in a controlled environment without electrical interference or external noise. While it might not necessarily be the culprit for audio clicks and pops, bad grounding in a room can create unwanted hum and noise. There are plenty of tools you can use to get rid of hum and buzz, such as balanced gear, isolators, and digital filters.

Best Audio Repair Software

Modern recording and mixing is pretty amazing. It's far easier to remove imperfections from audio recordings than it ever has been, all thanks to the wide variety of noise removal software solutions.

Peruse the market, and you'll find several plugins that have specialized features designed to identify and eliminate audio file imperfections.

• Adobe Audition has a comprehensive suite of audio restoration tools, including the "Auto Heal" and "Sound Remover" effects, which are great for mitigating clicks and pops. All you have to do is import your affected audio into Audition, select the noisy section with the Time Selection Tool, apply the Auto Heal function, and see the magic go to work.
• Audacity , is the best free option. With it, you get a basic yet effective toolkit for audio repair. The "Click Removal" effect, found under the "Effect" menu, is super easy to use. Select a problematic segment in your audio, apply the effect, and you're good to go.

Of course, even the best software isn't always as good as human ingenuity. In many cases, if I don't like the results I'm getting from one of the above programs, I'll take the manual approach.

Manual Editing

While it can seem mundane, taking the manual route is sometimes the best way to go. In the past year or so, I've stopped relying on de-essers when mixing vocals, instead opting to go in and adjust the clip gain on unruly sibilance. Though it might take a while, the results are always better and more transparent than if I were to use a plugin and automate the process.

The same goes for noise reduction.

Manually removing pops and clicks from an audio track is a meticulous process, though you get far greater control over the cleanup, allowing you to make precise adjustments that preserve the integrity of the original recording.

Here's my typical approach:

1. Open your audio file in your chosen audio editing software. I'm a Pro Tools user, though most DAWs or dedicated audio repair tools can do the job.
2. Zoom in on the waveform to get a deeper look at the audio in question. Many pops and clicks look like abrupt spikes or dips in the waveform. Compared to the smoother ebb and flow patterns you typically see in a waveform, they're easy to spot out.
3. Listen carefully to that section of audio on loop. I'll sometimes pause and replay sections to make sure I've identified the exact location of the noise I'm after. I'd recommend using headphones instead of studio monitors to make a more accurate assessment, as some noise might not be as easy to hear with sound bouncing around the room.
4. Select the problematic portion of the waveform. Most pops and clicks are pretty short, so your selection should be as precise as possible to avoid affecting any of the audio around it.
5. Apply a manual repair tool , if available. Some software has tools for pinpoint corrections, which can interpolate audio in whatever area you select to remove clicking from audio without leaving a gap. In Pro Tools, this is the smoothing tool.
6. Repeat the process for each click and pop you find. Again, this can be time-consuming, but if you want the most natural-sounding result, there is no better approach.
7. Preview your edits as you move through your track to make sure everything still sounds natural. Over-correcting is just as bad as under-correcting. If your audio sounds altered or degraded, undo the last few changes and try adjusting with a lighter touch.
8. Save your work as often as you can. I can't even begin to tell you the amount of times I've spent on editing and lost all my progress after weird plugin or system crashes.

Advanced Techniques

If you're dealing with a more challenging audio problem, you might have to employ some advanced techniques that go beyond basic click and pop removal. Spectral editing is one of the things that comes to mind.

While it might sound scary, it's actually relatively simple and one of the best methods for isolating and eliminating noise.

iZotope RX has excellent spectral editing tools that display audio in terms of frequency (vertical axis) over time (horizontal axis), rather than the traditional waveform view, so you can see the intensity of sounds across frequencies and easily identify noises that don't belong, such as clicks, pops, or even background hiss and hum.

I typically use the Spectral Repair module in iZotope RX if I'm dealing with pops and clicks that are either too subtle or too powerful for the normal De-Click module.

To use spectral repair:

1. Open your audio file in the Audio Editor and select the bad portion of the audio that you want to fix in the Spectrogram view.
2. After opening Spectral Repair module , compare the audio before and after processing to make sure it sounds right. If it does, you can click "Render" to repair it.
3. If Render did not work , you can adjust the parameter labeled "Bands." If you're processing signals with heavy transients or really short audio selections, I recommend using a smaller number of bands.
4. Try adjusting the surrounding region length to alter how much of the surrounding audio RX will use for interpolation.
5. The Multi-Resolution Mode can give you better low-frequency content interpolation and frequency resolution, so I'd also recommend employing that.
6. Finally, render your audio to commit any changes you've made.

I'm a huge fan of the Spectral Repair tool. I find it to be one of the most powerful pieces of software for removing stubborn clicks while retaining pristine audio quality, so that only the noise disappears.

Final Thoughts

Pop and click removal is a multifaceted approach, and if you're dealing with an audio track or audio recording with common noises like these, follow the steps above to remedy it. Whether you want to remove pops, mouth noises, or perform general audio cleanup, I'd recommend getting your hands on either Adobe Audition, iZotope RX, or Audacity.

Best of luck on your journey to clean and clear audio!