Feedback Emulator

Feedback Emulator is a free guitar feedback synthesizer for Windows (VST3). It gives a DI electric guitar the singing, blooming feedback of a cranked amp — in headphones, at bedroom volume, recorded direct into an audio interface.

The plugin does not loop or re-amp your signal. It listens to what you play — pitch, dynamics, sustain — and synthesizes the feedback from scratch: a bank of resonators tuned to the harmonics of the note, driven by a true self-oscillating loop with automatic gain control. The same physics that makes a guitar sing in front of a loudspeaker, modeled instead of miked.

Place it before your amp sim, on the clean DI signal.

Played with your hands, not the mouse:

• Leave a note ringing and the feedback blooms.
• Keep picking and it stays out of the way: the feedback ducks under active playing and floats back in about half a second after you leave a note ringing.
• Bends and vibrato steer the feedback tone; the Stability control sets how tightly it follows.
• Change notes and the feedback follows — a fresh tone grows on the new pitch instead of dragging the old squeal along.
• Hand-mute the strings to kill it, just like on stage.
• Low notes sing an octave up, like a real speaker-to-string loop.

Controls:

• Feedback amount, wet/dry Mix, Attack and Release envelope.
• Harmonic Mode: Natural, Fundamental, Octave, or Upper Harmonic.
• Growl — asymmetric saturation inside the self-excitation loop: the feedback thickens and snarls as it swells, and at high settings the harmonics audibly fight for dominance.
• Wander — slow, bounded drift of pitch and level, so a long sustain lives instead of standing on a laser-locked frequency. No two sustains repeat.
• Advanced panel: Sensitivity, Stability, Output Gain; Gate Threshold via host automation.

Five factory presets cover the range from a subtle sustain extension to octave squeals and ambient drones: Natural Sustain, Classic Rock Feedback, Octave Squeal, Harmonic Chaos, Ambient Drone.

Details:

• Monophonic pitch tracking (single notes work best; on chords it locks onto the dominant played note).
• Mono in / mono out — use it on a DI guitar track, before any drive.
• Windows 10/11 (64-bit, VST3).

Free for personal and commercial use.

{See video at top of page}

— Changelog
v1.0.1 (12 Jul 2026) Fixed: Broken, garbled feedback on stereo tracks. The feedback engine is a mono voice, but on stereo tracks it was being advanced twice per sample frame (once per channel), corrupting its internal state. The plugin now runs as true dual-mono: input is downmixed to feed a single engine, the feedback signal is shared by both channels, and each channel keeps its own dry signal.

v1.0.0: Initial KVR DC 2026 release.