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2. Simulating screaming guitar amp feedback

1 The distorted guitar feedback effect comes from the combination of guitar player and amp in a real space. When the sound coming from the amp is powerful enough to make the pickup coils and/or strings vibrate in sympathy, that sound returns to the amp, then back to the guitar, and so on, in one big feedback loop, until the amp can’t get any louder. 2 If you’re using a virtual amp, the only way to create a real feedback loop is to put the guitar next to your monitors, but in this tutorial we’re going to go fully virtual and fake the whole thing. There are a few clean guitar tracks to choose from in Tutorial Files – import one (or use a real guitar) and stick an amp sim of your choosing over it. 3 Softube’s Acoustic Feedback plugin has what we need to fake a feedback loop. Add it after the amp sim plugin. Acoustic Feedback sustains the signal in the same style as amp feedback, and can even account for changes and bends in the note. With Acoustic Feedback at its default settings, we immediately get some sustain out of held notes. 4 By pushing Acoustic Feedback’s

Feedback and Tolerance levels up, we can increase the virtual feedback amounts, making the ‘overload’ respond to subtleties such as vibrato in held notes. We can even get a sort of approximation of the effect at the beginning of Jimi Hendrix’s Foxy Lady. Who’da thunk it? 5 And because this is a plugin, we’re far less restricted than in the real world. In Acoustic Feedback, we can use the Dry/

Wet Mix knob, that lets us balance the amount of feedback we hear versus the amount of the original guitar signal. This can lead to some strange and disconcerting sounds. 6 Now that we’ve got a feedback simulator, there’s nothing to stop us trying it on more than just guitar sources. Try it on all sorts of synth patches to generate a panoply of sounds, from distorted and loud to weird and warbling.