We’ve added a new feature to Spotify today that many users have been asking for: the ability to turn off volume normalization. Volume normalization is used to try to keep a consistent volume between tracks but some users don’t like this. This new feature will allow you to choose whether you want music to be normalized or not, so feel free to test out both options and see which one you like the best. We’ve also increased the volume of music in Spotify by 3–6 dB when normalization is enabled to compensate a little more for the changes it makes to the volume.
To enable and disable volume normalization go to the preferences menu and uncheck or check the box and then press the Apply button.