iVolume for Mac

From Manfred Schwind:

iVolume improves the built-in 'Sound Check' function of iTunes to have your songs actually play at the same volume level.

iTunes uses a very fast algorithm to quickly analyze the volume of its songs. It's fast, but it's not very accurate. iVolume corrects the volume information that iTunes has calculated with better values. Therefore an algorithm is used that is oriented on the perception of the human ears. The result is a huge improvement of the 'Sound Check' function. You never have to readjust the main volume again when playing back your songs in random order. This is perfect e.g. for music on parties or hearing songs in random order with the iPod.