S/H LFO

A free-running, synchronized, or phase-addressed random curve generator with smoothing and controllable step correlation.

What it does #

S/H LFO reads a deterministic pseudo-random field as time or phase advances. With no smoothing it behaves like stepped sample-and-hold modulation; increasing smoothing blends neighboring random positions. Feedback changes how strongly values relate across an Epoch-sized distance, allowing slow Brownian-like drift or repeating structures.

Controls and ports #

Control	Label	Official description
smoothing	Smoothing	Amount of interpolation applied
feedback	Feedback	Correlation of successive output values, where positive settings trend toward small changes over time (à la Brownian motion) and negative settings can lead to repeating patterns
epoch	Epoch	Length of sequence (number of steps) used by the Feedback loop

Practical uses #

• Use Free or beat-synced mode for continuously changing random modulation with a controllable speed.
• Use Hold with an external phase ramp when the same random contour must repeat with a sequence.
• Apply positive Feedback for smaller related movements, or explore negative Feedback and Epoch for cyclic or alternating patterns.

Things to know #

• In Hold mode, phase is an address rather than an ordinary trigger: the same address returns the same value until the module's seed changes.
• Scaling phase beyond the usual 0-to-1 cycle accesses additional stable random positions; offsetting phase moves to another region of the same field.
• Retriggering changes the random field, so it can generate a new repeatable contour without changing the downstream patch.
• Positive Feedback favors related values across the chosen Epoch distance, while negative settings can emphasize repeating or alternating relationships.
• Smoothing is not a downstream low-pass filter; the recovered body reshapes the fractional address and performs cubic interpolation between four random positions.

Technical details #

A high-confidence Nitro implementation candidate supports the technical summary, but the visible-module mapping remains inferred.

The mapped lfo/sh_lfo/landom body treats its phase input as a 16.16-style address: the upper 16 bits choose step n and the lower 16 bits provide fractional phase. A seeded xorshift-derived hash maps each step to a bipolar value using 16 random bits, with the step index wrapped to 16 bits. Four adjacent values are combined by cubic interpolation after Shape remaps the fractional position. For nonzero correlation, each value R is replaced by R*(1-2*abs(c)) + R[n-epoch]*c + R[n-2*epoch]*abs(c), where c = correlation/3. The result is returned directly in bipolar mode or as 0.5 + 0.5*y in unipolar mode.

Nitro port	Type
in	InputAudioPortType
shape	InputAudioPortType
correlation	InputAudioPortType
bipolar	InputValuePortType
epoch	InputValuePortType
out	OutputAudioPortType
out1	OutputAudioPortType

Open questions #

• Map the visible Smoothing percentage exactly onto the internal Shape input and verify every timing mode in the wrapper.
• Measure retrigger ordering, seed persistence after save/reload, duplicate-module behavior, and polyphonic voice seeding.
• Confirm how the 16-bit step-address wrap appears at the visible phase input and whether stereo lanes share one field.

Version and sources #

Checked against Bitwig Studio 6.0.6. This page combines Bitwig's module metadata, the existing Grid course and guides, and Nitro analysis where the mapping is strong enough to support a technical statement.

Related material #

• Grid Modules course reference
• Is This the Best Method for Melodies in Bitwig Studio?

Return to Bitwig Grid Modules or the Grid Modules course lesson.