Sweet and Sour as Contrast: An essential ingredient for a full-flavored song.

The best example of this concept is the big trend in metal right now. Adding a more nasaly effeminate voice singing punk choruses in alternate to the main screamo voice. It's bizarre.

Then why are so many bands following this trend? Contrast. It's the most effective design principle, brought to music. A 1-note song instantly doubles in interest. A black and white checkerboard. A sans-serif headline with serif newsprint text. Contrast separates. Distinguishes. Adds another flavor.

In the slightly more mainstream world, we're seeing this as well, with odd voices taking center stage. Why? Simply because it's different. It creates interest. Dylan had it. Elvis had it. Whereas, every girl you see playing in a coffee house sounds the same. And they'll never stand out. But, The Tallest Man on Earth topped a lot of 2010 Best Music Lists with his latest album, which features the song, "King of Spain", embedded above. Why? Because the music isn't just good. But, it's a little weird, too.

In order to stand out, you have to be a little different.