How do you create feedback? Do you just need a guitar and an amp or is there something else I'm missing?
with high gain.
Quote by pedromiles101
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All you need is a pickup and an amplifier speaker.

It detail, though, it very much depends upon how resonant the frequencies in the guitar and the amplifier are. the acoustics of the room, the patterns of the wave forms of the two pieces of equipment and the distance between them also plays a part.

using distortion instantly starts to alter the oscillation pattern, thus aiding both natural and unatural feedback.

it only sounds good with certain amplifiers, though.
Last edited by AngryGoldfish at Jul 1, 2009,
There are various ways to help induce it. Higher gain being used, position in the room, amount of reverb going, and sometimes EQ.

Turning up the Gain I do not know the science behind, i'll be honest.

positioning yourself so that the guitars' pickups are receiving a loud enough signal from the speaker to be picked up again, many people find this is easiest when standing facing your amp speakers. I do this in my basement by walking out to a corner where tons of soundwaves tend to start bouncing. the point is, the vibration of the waves should be strong enough to be picked up again by the pickups.

Reverb aids in inducing feedback because of the same theory as above, its' reverberations already going through the amp, get the reverb strong enough and feedback will happen. Same idea as above, but in a more controllable fashion to us.

Note: Humbuckers, even coil split, are pretty hard to get feedback going at will.

2nd Note: A good way to get some feedback going from nothing (as if to start a song with) is taking a combo amp and tilting it up and down, pivoting it on its' back half. I don't know why, but it does just induce some feedback.
Quote by randomhero93
with high gain.

Not true.

Just turn your amp up loud and stand near it. If you want instant feedback, put your guitar against your amp.