MP3Gain is a graphical program for volume normalizing MP3 files. MP3Gain analyzes and adjusts mp3 files so that they have the same volume.
If you are tired of having to adjust your computer or MP3 player’s volume each time a new song comes on, you probably need to normalize your music collection. Normalization is the process of increasing or decreasing the amplitude of an audio file. MP3Gain does not just do peak normalization, as many normalizers do. Instead, it does some statistical analysis to determine how loud the file actually sounds to the human ear.