Guitar "sound" question. How to?

Question

I have been wondering for a while how to make this distinctive sound I often hear in a number of song.

Off the top of my head I can only think of one song which has a few of them, but I notice it a lot in Van Halen songs.

For example, in Pink Floyd's "Comfortably Numb" in the second solo, the first note David Gilmour plays is a sort of screeching sound an octave or 2 above what would you would "normally" play on that scale:

@4:28 in the video:

http://www.youtube.com/watch?v=YQWszrZHBPI

Thanks for any info

Answer 1

He used pinch harmonics

Answer 2

i think he used pinch harmonics.

also known as a squealie is a guitar technique pioneered by Roy Buchanan (typically electric guitar) in which the nail or thumb slightly catches the string after it is picked, cancelling the fundamental of the string, and letting one of its harmonics ring out. This creates a high pitched sound in any position. By using string bending, the whammy bar, wah-wah, or other effects, electric guitarists are able to modulate pitch, frequency, and timbre of pinch harmonics, resulting in a variety of sounds, the most common being a very high-pitched squeal. Pinch harmonics are generally considered a form of artificial harmonic, although in technique, they are different.

Answer 3

no idea. gotta love Gilmour though. sick song.