What's the best way to fix this audio?

smhontz wrote on 3/15/2004, 3:36 PM
I have a video of my son's school competition. The kids did a little play. They didn't speak very loud, so most of the audio is very soft. There are some parts where the parents clapped, and those parts are very loud. There is one part where someone tap-dances, and that's loud. And, during the middle of the performance, an air-conditioner turns on and it's pretty loud, too.

Thinking of several approaches to fix the audio.
1. Can I apply some overall compressor/some fx to bring the soft voices up, and the loud clapping down?
2. Should I split the clips into separate events, and normalize each separately? That way I could take the quiet sections and boost them.
3. Should I just use an audio envelope, and manually set it higher and lower to even out the volume?
4. Should I put the section with the air conditioner on a separate track, and apply Noise Reduction FX to just that section?

Any suggestions are welcome.

Comments

Jessariah67 wrote on 3/15/2004, 4:03 PM
The best thing to do is bring the soft parts up and dip the loud stuff. You can do this with envelopes, splitting clips or on separate tracks -- whichever works best for you.

As for the air conditionaer, you're probably stuck with it. Cutting out camera hum is one thing, but I've got a feeling that an AC unit is probably going to take a big bite out of the kids if you try to "get rid of it" with anything (either NR or EQ...)

HTH
Spot|DSE wrote on 3/15/2004, 4:46 PM
Nope.....NR will take out the AC and leave the rest intact. It will do this VERY well. Sony's FFT based NR tool is amazing, ask anyone who has attended our VASST classes showing this in very dramatic use. FWIW, NR is used for a lot of forensic work too.
Regarding the rest, you can cut sections and normalize, be aware you may need two tracks of the same audio to use to fade from the loud to quiet and vice versa. If you have WaveHammer, apply it at the master bus.
Save a small clip of just room noise that can be used for filler in any weird sections too.
Good luck!
GlennChan wrote on 3/15/2004, 5:21 PM
3 is just painful. 1 makes a lot more sense to me. You should be able to use the graphic dynamics or compressor plug-in to even out the loud sections (just compress the clapping a lot). I think the settings you should use are:
attack of close to 0
low release
curve (for graphics dynamics)- make it nearly flat at the top, and round off the corner by drawing lots of points. Find the loudest dialogue section and go far enough that you hear the compressor act on the dialogue, and then back off. This way it should leave the dialogue along but heavily compress the clapping.
The compressor plug-in has meters to help you out, and should be a lot easier to use. You can't get the soft knee in it (by drawing lots of points in the graphics dynamics plug-in) but it should be good enough.

I assume you don't have WaveHammer and don't intend to buy it.
TheHappyFriar wrote on 3/15/2004, 8:24 PM
I've done what you want to do (smhontz). I ended up cutting up the audio and making some parts louder, some quieter, etc. I did that instead of envelopes because you can see the waveform change when you normalize. I had a problem where the kids were quite and then when the teacher singing would hit certain parts, she was LOUD. :)

I never tried getting rid of AC noise. IF you're using Sony NR, READ THE MANUAL! it will make using NR a LOT easier. :)
ibliss wrote on 3/15/2004, 8:29 PM
One of the most useful controls on the NR plugin is the 'keep residule noise' check box - it lets you hear what audio is being stripped out while adjusting settings. Makes it much easier (i find) to hear what you are doing.
smhontz wrote on 3/16/2004, 4:51 AM
Actually, I do have Wave Hammer and the Noise Reduction plugins. Would you modify your suggestion now knowing that I have Wave Hammer?