Reducing the size of a .WAV file

I have a 20 minute recording. I am cutting all but about 2 minutes out. This gives me an MP3 file about 2 megs in size. How can I further reduce the size of this file. I have been told to change the sampling to 16 bit but I have not been about to figure out how to do that. I need a MP3 file at the end. I am emailing the file to places in the world where broadband is unheard of thus the desire for a small file size that has somewhat decent audio quality.

Any help is appreciated.


The size of an MP3 is determined by the bitrate. If you have a 2 minute file that’s 2Mb in size I’m guessing your bitrate is set to 128kbps. Reducing this bitrate will reduce the size, but sound quality will eventually suffer. If the file is simply speech then you can go quite low, but personally I wouldn’t use lower than 128kbps for music. However it is down to personal taste - experiment with the file and settle on what’s best for you.

If you are using Audacity 1.2.x, MP3 bitrate is set in Edit - Preferences - File Format. If you’re using 1.3.x, bitrate can be selected in the Options of the Export File dialog box.

Another common trick is to cut stereo loose and go with one channel mono sound. That will produce an MP3 half the size immediately. Oh, and audio compression software works best when you start with perfect audio, so don’t try to “help out” by compressing the audio ahead of time or capturing at a reduced bitrate. That always sounds terrible.

There is nowhere written that you have to use MP3, either. You can do very well with Apple AAC sound files, but it’s good to have either Macs or QuickTime at both ends of the job for that.


Or a copy of iTunes windows version (downloadable free) on your PCs.