How to use some of the tools in Audacity to improve the quality of your audio files

I use Audacity to record, edit, and clean up the audio for my podcast.  There are many options and settings in the application that allow you to change the way your audio sounds.  I haven’t figured out all of them but I thought I’d share a few of them that I’ve found helpful in improving the quality of the audio:

Noise Reduction - this effect allows you to eliminate static or noise that was recorded with audio.  In order for this tool to work effectively, you need to have a sample of 5-10 seconds of noise with no other sounds.  Most people choose to get this sample at the beginning or ending of the recording.  I recommend using this effect sparingly.  I usually leave it at one of the lowest settings if applying it to my tracks.  If you try to eliminate too much noise, your voices will end up having strange squeaks and almost robotic variations in the tone.  I think a little noise is better than that annoyance.

Compressor - this effect will even out some of the loud and soft peaks and valleys that occur in natural speaking.  Again, I recommend against being too aggressive with this tool because you can enunciate the static in your recording if you set the effect too high.  I generally don’t go beyond a 4:1 ratio at the most.  

Normalize - the compressor effect will bring your db levels to 0 by default.  Sometimes I find this to be too loud in comparison to the rest of my podcast depending on what the recording is.  Normalize will bring the levels back down to -3 db which I find to be a little easier on the ears.  I don’t use it all the time, but it’s definitely helped.

Amplify - I use the amplify tool to manually even out sounds when there’s a particularly loud segment in the recording.  This is particularly helpful with laughs or  excited exclamations in the conversation.  It can also be used to bring up a small section of the conversation if someone has lowered their tone for a short period of time.

Those are the 4 that I use the most often.  I’ll be the first to admit that I’m not an Audacity pro, but I have learned a lot in the past year of using it.  I’d love to hear additional comments from others who are using Audacity about the built in tools that they’ve found helpful.