I am creating ringtones by placing songs from my itunes library into garageband, trimming them down to the selected 30 seconds i want, compressing them into mp3s less than 300 kb in size (requirement in order to use as ring) using itunes, and then bluetoothing them to my phone.

My problem is that the volume is very low for these files. I have looked online and found services that increase the volume of mp3s without any "quality loss", but surely there is heavy distortion after the increase in volume. Raising the volume of the song in garageband before exporting it does not seem to change the volume once the song is in itunes, and changing the volume in itunes does not change the volume once the file actually reaches my phone.

Any suggestions?