I feel like there's something I'm missing and that I'm really dumb, but how do guitarists get there guitar to make that really high pitched, feedbacked scream that you hear in lots of songs? I don't really know how else to describe what I mean. If you listen to the first fraction of a second in Aquarian by Sleep, you can hear it (http://www.youtube.com/watch?v=V_0X6r64Ko4).

I just hear this sound sooooo often and the only times my guitar does it is by accident. It's probably a really dumb question, but I just want to know.
that's feedback. crank up the distortion and hold the pickup of your guitar next to your amp.
oh my bad. yeah that's just feedback. sorry about that
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