On my Windows 7 PC I made a playlist of YouTube videos and started playing them. One annoying problem I noticed is that some videos have sound that are much louder than others. Too loud in fact that I have to go and decrease the volume on the YouTube controls. I looked around and it seemed YouTube doesn't have any volume normalization feature built-in. Such a feature would put a ceiling of sorts on the maximum volume a video would output. Then I remembered seeing a feature in Windows that enables you to equalize volume for all audio on your system. This is how you get to it:
Go to Start, Control Panel (or click Start, then type in "Control Panel" on the search box at the bottom), go to Hardware and Sound, click on Sound, and you should see a dialog box similar to this:
click and select Properties
on your default Sound Playback device (which will have a green circle with a checkmark inside, and also say "Default Device"). Mine is the one that says "Creative Xmod".
On the Speakers properties dialog box that comes up, go to the Enhancements
tab, then check the box Loudness Equalization
, and click the OK button. Afterwards I found the sounds were on a much more equal level, or normalized.