Background noise can ruin the quality of your podcast audio and distract your listeners from your message. Whether it's a hum, a hiss, or a buzz, you don't want it in your final product. Fortunately, you can use software to remove or reduce background noise from your audio files. In this article, you'll learn how to use two popular and free tools: Audacity and Audition.
Before you start editing your audio, you need to choose the right software for your needs. Audacity and Audition are both powerful and user-friendly programs that can help you remove background noise from your audio. Audacity is an open-source software that works on Windows, Mac, and Linux. It has a simple interface and a noise reduction feature that can quickly and easily clean up your audio. Audition is a professional software that is part of the Adobe Creative Cloud suite. It works on Windows and Mac and has more advanced features and options for noise removal. It also has a spectral view that lets you see and edit the frequency spectrum of your audio.
Even before you choose software, you should be looking at your recording environment. No software solution can work miracles. You should design/build/chose your recording space in a way that prevents as much noise as possible from entering the microphones. This can be as simple as hanging blankets on the walls or as advanced as setting up a recording room with wall treatments, renting a studio space, or purchasing a room-inside-a-room kit that you can build. Once you have a good input signal, you can add your noise gate which should take care of all the noise your mics pick up when you're not speaking. Finally, make sure you have good gain structure! If you don't keep track and keep the signal at unity, you'll end up with audio hiss.
The first step to remove background noise from your audio is to record a noise profile. A noise profile is a sample of the noise that you want to eliminate from your audio. To record a noise profile, you need to have a few seconds of silence in your audio where only the noise is present. This could be at the beginning or the end of your recording, or in between segments. To record a noise profile in Audacity, select the noise-only portion of your audio and go to Effect > Noise Reduction > Get Noise Profile. To record a noise profile in Audition, select the noise-only portion of your audio and go to Effects > Noise Reduction/Restoration > Capture Noise Print.
The next step is to apply noise reduction to your audio. This will reduce or remove the noise that matches the noise profile you recorded. To apply noise reduction in Audacity, select the entire audio or the portion you want to edit and go to Effect > Noise Reduction > OK. You can adjust the settings such as noise reduction, sensitivity, and frequency smoothing to fine-tune the result. To apply noise reduction in Audition, select the entire audio or the portion you want to edit and go to Effects > Noise Reduction/Restoration > Noise Reduction (process). You can adjust the settings such as noise reduction, reduction level, and spectral decay to fine-tune the result.
The final step is to preview and export your audio. You should listen to your audio carefully and check if the noise reduction has improved the quality of your sound. You should also check if the noise reduction has affected the voice or other sounds that you want to keep. If you are not satisfied with the result, you can undo the noise reduction and try again with different settings. To export your audio in Audacity, go to File > Export > Export as MP3 or WAV. To export your audio in Audition, go to File > Export > Multitrack Mixdown > Entire Session or Selected Clips.