How to use audio compression?

rbc_tn wrote on 7/9/2002, 7:44 PM

I have some footage where the volume of the audio is very low. I'd like to boost the volume for the rendered final video. Obviously I can raise the track volume by up to 12 dB, and I'm assuming this will carry through to the rendered video (haven't tried it yet).

I'm wondering if I should also look at audio compression. There are points on the video where the volume is much higher for a few seconds. I'm afraid I don't understand how to use the controls in the Track Compressor - Input Gain, Output Gain, Threshold, Amount, Attack and Release. The online help is pretty skimpy - no background on how this works. And it appears that audio compression is not covered in the VV3 manual.

Anyone care to write a brief intro to compression for newbies?

Thanks!

- rick

Comments

Mike M. wrote on 7/9/2002, 11:20 PM

I could write many pages, but here's one of the best sites on the web I know of with lots of good topics: http://www.digido.com/

rbc_tn wrote on 7/9/2002, 11:32 PM

Thanks for the suggestion, but I'm afraid it didn't help much.

The site seems to be concerned with mixing music tracks - I neglected to mention that in my case the video is of a person speaking.

The only info I could find on compression (at http://www.digido.com/compression.html) doesn't talk about how to use the controls available in VV3.

- rick

BillyBoy wrote on 7/9/2002, 11:46 PM

The way I read your post it seems you just want to adjust the volume for a select area when the volume is too high or low. If so, the simpler way it just drop in a audio envelope. Insert-Audio Envelope-volume from the menu bar. That will add a blue line across the entire track.

Right click on the blue line where you want to change the volume. Add two points fairly close to each other. Now while holding down your left mouse button drag the second point up or down to raise or lower the volume. Add a third point where you want to change the volume down again, then a fourth. Again drag up-down left-right as you wish adding or deleting points as needed.

The track compressor is really intended more for adjusting the audio wave, which you don't need to do for what you want.

rbc_tn wrote on 7/11/2002, 12:41 AM

A volume envelope seems like the best option - and I even played with volume envelopes during the tutorial!

Thanks

- rick