We film weddings. For the first five minutes of a ceremony that we filmed, the wireless mic on the officiant had some interference. It pops about every five seconds. The frequency it's on is higher than the officiant's voice, so it seems that one could take that frequency down and improve it. Are there any tools on FC7 that would enable me to do that? Tx
If the pops aren't too frequent, you can sometimes minimize the popping bu expanding the audio waveform and manually setting keyframes to quickly drop the level and then bring it right back up again. It won't completely eliminate them but it can minimize their effect.
Short answer: yes, you could use several audio tools right within FCP7 to handle this. The notch filter, the AU High Shelf filter, the parametric EQ, the multiband compressor, notch filter and noise gate filters will all help. Some will also have an effect on the rest of the audio around the "hit".
Longer answer: While I'd start with the notch filter, it may be that another technique will work better for you: grabbing a few frames of clean audio just before or after the hit, and pasting that directly over the top of the "bump", on a new audio track. Then mix between the two until it sounds good. Once you have this down for one instance, you can copy/paste it over all the other "bumps, or at least most of them.
Apple Soundtrack is a good tool for audio repair. The free Audacity app is perhaps easier for a beginner to work with.
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