Software to increase the decibel level/loudness of multiple songs at once?

[Kadence]

I have a group of a few dozen songs, all of whom I'd like to make louder. I currently use Audacity to edit the DB level of a song one by one, but don't know of a way to mass edit independant files. Is there any software that can increase the decibel levels of a group of songs at once?

 

[PowerEngineer]

http://mp3gain.sourceforge.net/

Works for me!

 

[Dahak]

http://mp3gain.sourceforge.net/

Works for me!

2nd, i've used that for years to level out the the volume of my music. nothing worse than having a moderate volume level song and then it hits a really lout part

 

[Kadence]

Works for me!

Thank you