How to Equalize All Song Volumesby Seamus Islwyn ; Updated September 22, 2017
When two songs are mastered at different levels, their volume levels sound different when you play them back. The process of equalizing the volume levels of different songs is called "normalization." When you normalize a list of songs, your media player plays them all back at the same volume level. If you use the iTunes or Foobar2000 media software to listen to music, you can equalize the volume of songs using their built-in utilities. If you use a different media player, download and install the MP3Gain utility, then use it to equalize the volume of the songs.
Launch iTunes. Open the "Edit" menu and select "Preferences."
Click the "Playback" icon. Check the box next to "Sound Check."
Click the "OK" button. Double-click a song in your iTunes library to start playing it, then double-click a song from a different album to hear the normalization effect.
Launch Foobar2000. Open the Edit menu, then click "Select All" to select all of the songs in your Foobar2000 library.
Right-click one of the selected songs. Hover the mouse over "ReplayGain" and select "Scan selection as albums (by tags)." Foobar2000 scans the volume information of all the songs in your library and determines their relative volume levels.
Open the File menu and click "Preferences." Click the "Processing" drop-down menu and select "Apply Gain."
Click-and-drag the "With RG Info" slider to "0." Click "OK" to apply the settings, then double-click a song to start playing it.
Download, install and launch MP3Gain. Click the "Add Folder" button, then click the folder containing your MP3 collection in the browser window that opens. Click "OK."
Press "Ctrl+A" to select all of the songs. Click the "Track Analysis" button to analyze their volume levels.
Click the "Track Gain" button. MP3Gain adjusts all of the songs to an equal volume.