Re: Controlling feedback?
"Stand in the right place" is easy at home or rehearsal, but not as easy live for a couple reasons: 1) sometimes small or cramped stage, 2) sometimes not much of a soundcheck before launch, 3) sometimes monitors mess with it. But when you DO hit it...bliss.
I had not played live in front of an audience since 2001 and last March we got back together for two shows. At the first show, nothing. Small stage, so-so sound system. At the second show with a much bigger stage I managed, mostly by accident, to find a spot that would give me infinite sustain/feedback for high notes. That was a much better night for me.
Equipment and technique are more important in my opinion. Some guitars just resonate better and are more lively. Some amps crank out the right frequencies to get that guitar humming. The right combo can overcome most of the obstacles I mentioned above. I had a '62 SG with a Super D pickup and I could sustain pretty much any note at any volume as long as I wanted from anywhere in front of the speakers just because of the way it interacted with my amp. Even unplugged I could keep a note going forever on that guitar with my Stunning Finger Vibrato (r). I had a couple other guitars at the same time that just would not go there. The right combination is magic. The wrong combo means doom and failure.