The audio side of video is often not well recorded due to small production budgets and short time frames. Therefore, during post-production, producers can be assaulted by a series of previous sonic missteps. An annoying rumble or hum in the low end is a common problem in audio recorded for video.

Certainly many of the software plugins on the market that filter out noise work very well. Though, under a tight deadline, it may prove impossible to seek out, purchase, and learn the functions of whatever new plugins you may find. As an easy alternative, use the standard eq and reverb plugins provided in your video or audio software.

Use standard package plugins and the following tips to eradicate nasty noise from the bottom end of your audio recordings:

Use a Single Band EQ first to cut out the unwanted rumble. A single band EQ will filter out all audio above or below a specified frequency. You can cut out, for example, all frequencies below 80 Hz in order to erase much of the rumble, which occurs at 60 Hz, without harming dialog tracks.

Secondly, a Parametric EQ can be used to “notch out” the unwanted noise by decreasing a thin width of audio frequencies and its octaves such as 60 Hz, 120 Hz, and 240 Hz. The advantage of using a Parametric EQ is that one can notch out the offensive noise without hurting wanted audio.

Secondly, you can boost the desired audio also by using a Parametric EQ. This will give the wanted audio prominence over the unwanted audio. Once can boost the dialog at 5 hz slightly, for example, to give it prominence over a low rumble.

Fourth, once the low end has been cut or minimized, use a bit of reverb on the entire mix. This creates a sonic wash of sorts and reduces the “tin can” effect that can be created by cutting out the low end.

Following the above strategies may not completely erase all problems associated with bad audio, but they can improve the quality of the product when unwanted noise and dialog are competing for attention in the mix.