As this answer demonstrates, SOX works for this.
However, it is painfully slow and does not offer to correct (i.e. normalize) the offending files in the same process, therefore:
I love easyMP3Gain for normalizing MP3s !
Unfortunately, there seems to be no package for 17.10 Artful, but luckily the GUI packages for 16.04 Xenial are compatible and you can find them here!
This is probably not best practice but what I did was..
wget <your favorite ubuntu repo server here>libqt4pas5_2.5-15_amd64.deb
wget <your favorite ubuntu repo server here>easymp3gain-data_0.5.0+svn135-6_all.deb
wget <your favorite ubuntu repo server here>easymp3gain-qt_0.5.0+svn135-6_amd64.deb
Start with the libqt dependencies but install all the packages like this :
sudo dpkg -i libqt4pas5_2.5-15_amd64.deb
you will have to run sudo apt-get --fix-missing
and sudo apt-get --fix-broken install once or twice to get all the libqt dependencies, and then rerun the dpkg -i commands
Once you are able to run easymp3gain you can get the source for mp3gain from sourceforge here, untar it. Change directory to the extracted files and make sure you have the build tools installed
sudo apt-get install build-essential
then build it with
sudo make install
You might need to copy the binary, at least I had to do that
sudo cp -p mp3gain /usr/local/bin/
Now you can run easymp3gain-qt ! Just select the folder with your MP3s and sort by Volume !
Screenshot of easyMP3Gain sorted by volume
I hope this helps !