Music Composers Unite!
You can get switch sound file converter.
This is complely free and will change your wav files to mp3 under 10mb
Surely you must be saving audio in .wav format to be creating such big files.
If you save as > mp3 the files are normally compressed to around 10% of the original size.
This will have an effect on quality but not usually enough to turn music into mud and is now the audio compression, anyone would expect to get when buying a downloaded track or album on iTunes or whatever other online shop we use.