Can Audacity Do These Things?

[tinker123]

If a recording is made at a low volume, can audacity "raise the volume", make the recording louder?

Can audacity clean out the background noise in a recording?

For example, could I get rid of the static in this recording using audacity?
http://www.youtube.com/watch?v=Iw3sDgaoBeA

[kozikowski]

Yes, you can use Audacity to put the performance volume wherever you want it. I suspect it may be harder to solve the problem where the doctor leaned into and away from the microphone. You may need to solve that one minute by minute by hand.

Both Effect > Normalize and Effect > Amplify will change the volume of the whole show at once automatically or to volumes you specify.

The Envelope Tool (two white arrows and bent blue line) can be used to change the volume of the show word by word. The blue lines are rubber bands and they can be pushed up and down for detailed volume changes.

The background noise. That's harder. What usually happens is somebody posts with a performance that's completely destroyed from sound problems, but that's not how this one works. I would have no trouble listening to that lecture just as it is. Is there a specific reason you want to "clean it up?" If you present a difficult show for cleaning, it's not unusual for the cure to be worse than the original show.

Koz

[kozikowski]

I'm going with no. I can help a little with the noises between the words, but the doctor is always going to have a ratty voice with static and bumps in it. The doctor spent the first few seconds of the lecture finding and putting on his microphone and that will be very difficult to fix. It sounds a little like somebody already tried to patch up the show and that's what's causing the noise breathing during the performance.

For maximum effectiveness, it's good to get to the problem first.

So if you want to go word by word through the lecture, you could probably get marginal improvement. We can show you how to do that.

Koz

[kozikowski]

He's pretty interesting. I may listen to the whole thing.

I got this. He put his lavalier microphone on wrong. You're listening to his jacket rubbing against the microphone. He also bends forward and back and folds the mic behind his lapel and then reveals it. That's when his voice get muffled and then gets sparkly and crisp.

This is the poster child of how not to use a lavalier microphone; he's making pretty much all the mistakes. You should not use a lavalier like this because it's almost impossible to fix the damage in post production.

I see it's an hour and a half show. That can't take you more than a couple of weeks -- and it will never sound like a studio production.

Koz

[tinker123]

If you present a difficult show for cleaning, it's not unusual for the cure to be worse than the original show.

Gotcha. I will leave it alone. Thanks.