Adjust Sound Levels in Audio Recordings With Levelator
Do you have a niggling little issue constantly cramping your workflow? You know what I'm talking about -- every time you use your favorite program, you remember it's missing that one small feature that would make it perfect. Don't you love it when you find an app that fills in that gap? Me too.
While creating podcasts, I frequently record conversations over Skype, then import them to Audacity for editing. One of the primary issues I consistently encounter is a difference in the sound levels among callers. It's important to even out the sounds during editing to make for a pleasant listening experience once the podcast is live. Audacity is good at a lot of things but, unfortunately, not this. It does have tools for equalizing and normalizing, but it doesn't even out sound levels well at all.
Luckily, I found Levelator. According to the app's Web site, this tool "adjusts the audio levels within your podcast or other audio file for variations from one speaker to the next, for example. It's not a compressor, normalizer or limiter although it contains all three." It's not open source software, however it's one of the few free tools I've found that runs on Linux (as well as Mac OS X and Windows) to get this particular job done. It was built and tested on Ubuntu Feisty Fawn, but I've had no issues running it on openSUSE 11.0.
Using Levelator is a no-brainer. Simply download it, drag and drop your WAV or AIFF file onto the desktop icon. It does all the work for you, then spits out a new version automagically.
If you're looking for a tool to edit MP3's, Levelator isn't for you. As one of the developers points out on the Web site's forums, processing MP3's with Levelator would result in a "substantial loss in quality" because of decoding / re-encoding issues.
If you're new to podcasting on Linux, or looking for additional recording tips, be sure to check out Sam Dean's post for 15 free tools that help get the job done.