One of the most iconic techniques in instrumental rock guitar history; the Satch Scream. It's one of Joe Satriani's favorite techniques and one that has made him famous. It consists of doing a pinch harmonic below the neck pickup while pushing and pulling on the whammy/tremolo bar in order to get a high pitched scream. It is best done with a Floyd Rose tremolo or any other type of floating tremolo system while having the guitar on the bridge pickup position.