When using feedback in an audio system, what effect can it create?

Feedback in an audio system occurs when a portion of the output signal is fed back into the input in a way that amplifies it, often resulting in a distortion effect. This can happen when the sound produced is re-captured by the microphones or pickups and is then amplified again, leading to an increase in gain that causes the signal to clip or distort. This effect is often characterized by a ringing or howling sound, particularly when it is unintentional.

While feedback can indeed influence parameters like volume, stereo separation, or pitch modulation in various contexts, its most notable and recognizable outcome is the distortion effect that results from excessive feedback loops. This is why it is commonly used in music production to create unique sounds or textures, but it can also lead to undesirable outcomes if not controlled properly.