ZZ Top has a song called "LaGrange," which has a guitar solo at the end. This particular stretch of music has a higher pitch, sounding almost like sighing at top volume. I've always wondered how guitar players produced that particular sound.
I play stand-up bass, and I used to jam with other musicians. One guitar player named Mike had the looks, the long hair, and the rock star attitude for sure. During one jam session, he started playing LaGrange, and I asked him how he gets that high pitch at the end.
He just smiled and said "You gotta believe."