Fixing Noisy Camera Audio During Video Editing with Noise Reduction
How you can take low quality camera microphone audio and turn it into something that’s at least useable for YouTube videos. We’ll go over noise reduction techniques, as well as equalization and compression to make it sound a lot better, that way you can have better quality audio on your videos without having to purchase a new microphone right away.
For this tutorial, I’ll be using Adobe Premiere Pro and Audition to process the audio. There are free alternatives like Audacity as well, as we’ve done a video on noise reduction in that program, but it doesn’t work quite as well. To start, we’ll open our video editing project and import our video file with the audio we want to process. Then, right click on the audio file and select edit clip in Adobe Audition. This will open up Adobe Audition and allow us to edit the clip.
Then we can save it and it will automatically link it back to the Premiere Pro project. Now that we’ve got our clip opened, we can see that there is a considerable amount of noise. The first thing I want to do is get rid of that noise. Select only a selection of noise from the beginning of the clip. Then go to the Effects menu and select Capture Noise Print under Noise Reduction.
Now we’ve told Adobe Audition that this is the noise we want to remove. Go back to the Noise Reduction menu and select Noise Reduction (process). First I set the smoothing to 2. This change reduces the amount of noise reduction that is applied, but gets rid of some of that background bubbly artifact sound that noise reduction can cause I find a small amount of remaining noise is a lot more tolerable than these obvious artifacts.
Especially with this camera audio, we have a lot of noise so cleaning this problem up is very simple. The other thing I do on this track is lower the spectral decay rate to 60%. Otherwise I get what sounds like a bad reverb sound In this case, it’s a lot cleaner without it. This also kind of balances with some of the other tools, and if you don’t get it right it makes it sound like you have a cold.
I also find that it helps to bump up the precision factor to 15 for this track. Finally, we need to set it to reduce noise by 100 dB, otherwise we get residual artifacts and it actually ends up sounding worse the less noise reduction we apply. So at this point, we’ve made a big improvement to the audio quality out of this camera, but at the same time we’ve slightly damaged the frequency response. This isn’t too drastic, and it’s a necessary step in this case to really clean up the audio. To fix this, I’m just using a parametric equalizer.
I start with the vocal enhancer preset I’ll back off the high pass filter that’s cutting the low end out, since our track is already lacking in low frequencies due to the poor camera mic. Then I want to get rid of that boxy sound, so I make a cut between 200 and 250 Hz, depending on where it sounds best. Finally, I bring down that high shelf and add a little just over 2500 Hz to liven it up a little. The last thing I like to do is bring up the level with the single band compressor.
I use the voice over preset and adjust the gain to bring it to around -3 dB, without any clipping. You may need to use more compression or less gain, if you find the track is clipping. This just gives us a much more useable level. Don’t go too far with the compression, or any remaining noise or artifacts will be amplified and make the problem worse. If you want to get rid of any additional noise between words, you can use a noise gate before the compressor and that will also get rid of some of the artifacts.
Just be careful with this, since it can cut off the beginning of words if you don’t have a lookahead option. After that’s done, just save the file and exit Adobe Audition. It will automatically be sent back to Premiere Pro Keep in mind this isn’t perfect, and this is recording is done under ideal conditions. I’m not defending the use of the built in camera microphone, just presenting some options that could help.
The audio quality definitely isn’t anywhere near a dedicated mic, but it is quite a lot more useable after some quick processing like this. The end result is useable camera audio right out of the built in microphone It’s not perfect, but if you’re using it for something like YouTube, the processed sound is good enough and any small imperfections can be hidden with some light background music Of course the best solution is to record the best audio you can in the first place, and that means upgrading to a better microphone. For all my videos, I’m using an MXL990 large diaphragm condenser microphone.
This is an XLR microphone that can plug into an audio interface, but they also have a USB option available. It’s great for indoor use when you’re doing voice over.