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

v1.0.2 (07 Sep 2026): The plugin interface no longer runs in an embedded WebView2 browser. It is drawn natively by JUCE instead, so the window opens faster, uses less memory and does not depend on the WebView2 runtime being installed. Hosts that showed a blank or white plugin window now render the UI correctly.

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.