Free tremolo and auto-pan plugin: movement in time with the track
Tremolo moves the volume up and down; auto-pan moves a sound between left and right. Both turn a static part into one that breathes with the track. Here's how to set them, and free plugins that do both.
COLONY: the free multi-effect plugin from 13x Audio
Add warmth, width, space and movement to drums, keys, bass and loops — six effects in one plugin, moved together by one ENERGY knob.
Tremolo and auto-pan in a nutshell
Both are driven by a modulator - usually an LFO, a slow repeating wave. For tremolo it moves the level, for auto-pan the position in the stereo field. Rate sets how fast it repeats, depth how far it moves.
Synced to the project's tempo, the movement lands on the beat; free-running, it drifts against it, which suits ambient parts more than grooves.
Shapes, rates and swing
- Sine and triangle: smooth, even movement - classic tremolo on keys and guitars.
- Square: hard switching that chops a sustained part into a rhythm.
- Saw up or down: ramps that swell or fall away on every cycle.
- Random and step patterns: a new value on every step, for movement that doesn't repeat obviously.
- Eighths and sixteenths sit inside the groove; triplets and dotted values pull against it. Swing pushes every second step late, like a swung hi-hat.
Keep it musical
- Start with less depth than you think; a little movement reads clearly in a full mix.
- Auto-pan the supporting parts - percussion, arps, pads - and keep the lead and the low end in the centre.
- Listen in mono: auto-pan can turn into a level change when the channels are summed.
Tremolo and auto-pan in COLONY
COLONY's MOTION Cell drives one target at a time: Tremolo, Pan (an equal-power auto-pan), Stereo (which moves the width), Filter (a resonant low-pass sweep) or Wow (a pitch wobble). The modulator runs as an LFO, a step sequence of 2 to 16 steps or a random source, with Sine, Triangle, Saw Up, Saw Down, Square and Smooth Random shapes.
Rates sync from 1/32 to 4 bars, including triplets and dotted values, or run free from 0.02 to 20 Hz, with Swing, Phase, Depth and Mix on top. ENERGY can deepen the movement as the arrangement builds.
What it doesn't do: MOTION modulates one target at a time; its tremolo dips by up to about 26 dB and never mutes completely, so it isn't a hard trance gate; and its filter is low-pass only.
Other free tremolo and auto-pan plugins
All free, as their makers list them (checked 2 October 2026). Some need an account or an email address to download.
- PanCake 2 · CableguysOfficial page ↗
An auto-panner driven by LFO shapes you can draw.
Free (enter an email; Cableguys creates an account) · Windows, macOS · VST2, VST3, AU, AAX - MFreeFXBundle (MTremolo, MAutopan) · MeldaProductionOfficial page ↗
A free bundle of effects that includes MTremolo and MAutopan.
Free (the free version shows a reminder; a paid upgrade removes it) · Windows, macOS · VST, VST3, AU, AAX - Flux Mini 2 · Caelum AudioOfficial page ↗
A shape you draw modulates filter cutoff, resonance, volume and mix in time with the track; Caelum mentions sidechain-style use.
Free · needs a Caelum Audio account · Windows, macOS, iOS · VST3, AU, AAX
COLONY: the free multi-effect plugin from 13x Audio
Add warmth, width, space and movement to drums, keys, bass and loops — six effects in one plugin, moved together by one ENERGY knob.
What is the difference between tremolo and auto-pan?
Tremolo modulates a sound's volume; auto-pan modulates its position between left and right. Both usually use an LFO, with a rate and a depth.
Should tremolo be synced to the tempo?
For rhythmic parts, yes - synced rates like eighths or sixteenths keep the movement in the groove. Free-running rates suit ambient parts, where a slow drift against the beat sounds natural.
Is auto-pan mono compatible?
Partly. When the channels are summed to mono the panning disappears and can become a small level change, so check the part in mono and keep the depth moderate.
Does COLONY have a tremolo and an auto-pan?
Yes. COLONY's MOTION Cell offers Tremolo and Pan targets, plus Stereo, Filter and Wow, with LFO, step and random modulation synced to the tempo or free-running.