Originally Posted By: etcjoe
There are certainly wrong notes, that just don't sound good. Dissonance is one thing, just plain awful is another. I once was in a place where a guy starts playing the piano, but the background music was still playing over the ambience speakers. Talk about dissonance and wrong notes! 2 songs played at once can do that to you!!

Makes me think of Charles Ives and his family music exercises. That'll toughen him up!