View Full Version : Post production help for a commercial


Scott Hamilton
March 15th, 2010, 10:21 AM
Hey guys. I shot a commercial in a grocery store last week. I recorded my actors audio with the Rod VideoMic on a boom pole, and had it just right out of the frame, mostly close up shots of them.

I have a bad buzz going pretty constantly, probably from the lights overhead. There is no other bad audio, we shot it before they opened, but is there anything I can do to reduce that buzz sound? It's kind of a low hum. I can post a sample clip if it would help. I'm editing in Final Cut Express. Thanks!

Scott

Shaughan Flynn
March 15th, 2010, 10:52 AM
Try a high pass filter. Put headphones on and move the FREQ slider UP until you reach the point where the low hum is gone and the vocals are not distorted. Another method is to EQ the audio and cut the low end to get rid of the sound (essentially doing a high pass with an EQ) and finally, if you have a noise reducer, just set the noise print of the hum and run the noise reducer on the clip and adjust until the hum is minimized and the vocals still sound good.

One of the things I ALWAYS do before shooting at a new location is to take my audio rig over there and record room tone so that I have an idea of what I will be facing and can try to mitigate any issues before hand.

Shaun Roemich
March 15th, 2010, 10:56 AM
If FCE ships with Soundtrack Pro, use the Noise Print function to identify the free standing sound as a noise print and then select the entire range and reduce the noise.

Shaughan Flynn
March 15th, 2010, 11:59 AM
FCE does not come with STP. It does, however, come with some audio tools:

From the Apple web site:

Further enhance your audio with such included Audio Units filters as Reverb, EQ, Echo, and Delay. The new Soft Normalize and Gain feature analyzes sound clips, automatically raising clips to their maximum level without distortion. You can even adjust audio filters in real time, listening to your work in progress and modifying it as the track plays.

So you should be able to use the EQ function, worst case...

Or get a copy of the open source DAW app Audacity (http://audacity.sourceforge.net/).

Scott Hamilton
March 15th, 2010, 12:46 PM
Thanks a ton guys. Lots of good methods, I will try them after work and see what works best. Thanks again!

Jon Fairhurst
March 15th, 2010, 01:18 PM
Unfortunately, 60 Hz buzz like that is hard to remove without making your dialog sound underwater. If it's just a low hum, it can be removed. but a buzz will have broadband noise.