AvailableEffect

Auto Panner

Move a signal across the stereo field.

@maru shared this effect so you can play it in your DAW, remix it or put it on your site.

Play

What it does

Auto Panner moves a sound back and forth between the left and right speakers. A sine wave sets the position, so a single mono source comes out as a stereo signal in motion.

The idea

Panning is the oldest way to make one sound occupy two speakers. A panner builds the two channels itself, so this works on a mono guitar, voice or synth without needing a stereo source.

Rate behaves like two effects. Below about 8 Hz your ear follows the movement and hears a position travelling. Above about 10 Hz the movement is too fast to track and turns into a rough texture with a stereo edge. The range goes up to 20 Hz so that end is reachable.

Guide and controls

How it works.

A sine LFO at Rate drives a stereo panner's position between full left and full right, with Depth scaling how far from centre it goes. That is the entire effect, it is amplitude modulation applied in opposite directions to two channels, which is also why a tremolo with its channels 180 degrees out of phase turns into one.

The browser preview runs it on a StereoPannerNode with the LFO summed into its pan parameter, all at audio rate. A panner constructs the two channels rather than requiring them, so this works on a mono source, which is the difference between this module and Stereo Widener, whose matrix has nothing to scale unless the input already carries a side signal.

Depth at 1 reaches hard left and hard right, and at the panner's equal-power law that means each channel is briefly silent while the other is full. Pulling Depth back keeps both speakers contributing throughout, which is usually what a mix wants; the extremes are more useful as an effect than as a placement.

What would you make with Auto Panner?

Describe what you want to make. Build it with the Studio agent.

Part of Physics Playground

Goes well with.

Building block

Tremolo

Periodic amplitude modulation with stereo phase control.

Building block

Stereo Widener

Adjust stereo width without changing the dry signal.

Prototype

Space Mini

Convolution reverb: eight synthesized spaces, twenty-five real cabinets.