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Build: LFO Modulation

A low-frequency oscillator modulation source. A slow oscillator generates a periodic control signal. The mul node scales its depth and the add node shifts its center point, producing a modulation signal ready to connect to any parameter — filter cutoff, oscillator detune, or gain level.

Step 1: Add a slow oscillator

Section titled “Step 1: Add a slow oscillator”

Set the osc frequency low (2 Hz) — this is not an audible tone, it is a control signal that sweeps back and forth.

Nodes added: lfo-osc

Step 2: Scale the depth

Section titled “Step 2: Scale the depth”

The mul node multiplies the oscillator output (±1) by a depth value, controlling how wide the modulation swings.

Nodes added: lfo-mul

Connections: 1 new

Step 3: Shift the center

Section titled “Step 3: Shift the center”

The add node offsets the signal so it sweeps around a center point instead of around zero. For filter cutoff, set center to 1000 and depth to 500 for a 500–1500 Hz sweep.

Nodes added: lfo-add

Connections: 1 new

Step 4: Group into a module

Section titled “Step 4: Group into a module”

Select all three nodes and press g. Expose the add result as output, and Rate, Shape, Depth, Center as parameters.

What you just built

Section titled “What you just built”

A reusable LFO Modulation module with 4 exposed parameters and 1 exposed port.

Select it in the Module Library (SPC m) to add one to any patch.

Next steps

Section titled “Next steps”