I recently went to a bass workshop. The teacher introduced the concept of overtones as a tool to help with intonation. When the right note sounded the overtone of several different notes would sound on different strings, but some notes didn't have an overtone. He said there was a pattern to which notes had overtones and which didn't, but I guess I jus didn't really understand what he was trying to say. Could someone please explain to me the concept of overtones and the pattern of when they sound?