How to Fix Bad Audio Quality from Video | Big Pi
What is room noise? Simply put, room noise is whatever ambient sounds that are constant (and sometimes not so constant) and present in the room in which the video was shot. Sounds like refrigerators, lights, traffic, crickets, fans and even camera noise can all be considered room noise. This noise rarely completely ruins a recording, but it can make listening to dialog or voice more difficult, and even muffle the sound of the voice altogether.
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Like distortion, in the old days we used to use EQ to help with runaway room noise. We do this by finding the frequency of the noise(s) and rolling them off. The problem with this procedure is that you’re also rolling off the good sound of the voice. And because we have to use very narrow “Q” or widths, it creates weird phasing effects in the final sound of the recording.
A much better “old-skool” method to remove background noise from audio is the implementation of an expander. An expander or noise gate (either one) opens as the voice crosses a threshold, and closes after it stops. This allows the noise to be masked by the sound of the voice and immediately be cut off when the voice stops. Ideally, the threshold of the expander/gate is set just below the lowest volume of the voice so that no part of the performance is accidentally “cut off.” Then a short attack with a quick release and a few ms of hold allows for the expander/gate to open and the voice to be heard.
When the voice stops, the expander/gates close tightly after the end of the last syllable or room ring. This method works well when the noise is moderate, and the recording is well done. However, if the recording is low volume, or the noise is excessive, expanders and gates sometimes exacerbate the situation by introducing “pumping” noise every time the voice is heard.
The modern method of removing room noise from recordings is using plugins. For constant noise, the simple use of an algorithmic de-noiser like the ERA 5 Noise Remover or ERA 5 Noise Remover Pro are highly effective ways to remove background noise from audio.