Soundcompare allows you to select 2 different or similar sound files for comparision visually. It will show the difference when you click the Filter button. If you click Xray it will allow you to see easily the overlap in sound and in the future alter the sequence selected.
I wanted to build something that allowed me to compare sound quality between Dolby Digital Plus and other codecs. It turned into something really fun!
Check the code out and run the index.html file and you should be good to go.