One Slider

DOUBLER

Automatic Double Tracking

Download free Part of NULL JSFX 2.5: 113 plugins, free and open source (MIT). Easiest with NULL JSFX Hub.

Listen

The same music with the Wide Mono Guitar preset and without the plugin. Switch while it plays.

Controls

Amount0 to 100 — Level and width of the two doubles: 0 is the dry signal, higher values make the left and right copies louder (up to 80%) and push their delays later (about 14–20 ms and 21–29 ms)

Best uses

Fake a double-tracked vocal
Widen mono guitar parts
Thicken backing vocals
Stereo spread for mono synths
Subtle width on lead lines

Properties

Input → mono sum → two delayed taps with slow independent drift (0.13 Hz / 0.21 Hz) → one double added left, one right → level compensation → Output. Original stays centred; zero latency.

Formats

JSFXJSFX for REAPER, with REAPER's own sliders
GFXJSFX GFX for REAPER, with its own interface
VST3VST3 for any DAW
CLAPCLAP for any DAW

Factory presets

Lead Line Width · Vocal Double · Backing Vocal Stack · Wide Mono Guitar · Synth Spread

In the FX chains and Rack presets

Ensemble · Harmony Stack · Pop Vocal · Six-Fader Vocal · Vocal Chain

See every FX chain

Try it

Try it on orOS StudioAdd it to a track in your browser, with its own interface. Nothing to install.