Wavetable LFO

A morphable LFO that scans a loaded Bitwig wavetable as a repeating modulation shape.

What it does #

Wavetable LFO reads one cycle from a selected position in a WT wavetable. Phase moves across the current table, while Index chooses or morphs between the tables in the file, allowing the modulation waveform itself to change over time.

Controls and ports #

The shared LFO controls provide Rate, Timebase, triggering/synchronization, phase, polarity, polyphony, and modulator output. Wavetable selection and Index choose the shape. Inspector options can latch Index for a complete cycle and control whether each table's end is wrapped toward its beginning.

Practical uses #

• Load a wavetable containing contrasting shapes and modulate Index slowly to evolve the modulation contour.
• Enable Hold Shape During Cycle when Index changes should take effect only at cycle boundaries instead of bending a cycle in progress.
• Use pitch-rate and bipolar operation for audio-rate modulation or as an experimental oscillator/control source.

Things to know #

• Phase and Index are different axes: Phase scans one waveform, while Index moves through the collection of waveforms.
• Hold Shape During Cycle latches the Index at phase wrap, so one complete cycle uses one stable table position.
• Don't Wrap Tables preserves a difference between the last and first sample of a table; this can create a jump when phase wraps.
• The raw wavetable may contain oscillator-oriented shapes, but at ordinary LFO rates they become modulation curves.
• Audio-rate operation can expose interpolation, discontinuity, and anti-aliasing behavior that is insignificant at slow modulation rates.

Technical details #

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

The confirmed grid_wavetable_lfo_table_index helper first clamps the modulated index as index = clamp(index_in + table_amount*table_mod, 0, 1). With cycle latching disabled, that value passes through continuously. With latching enabled, it detects a phase wrap when previous_phase > current_phase and updates the held Index only on that sample; otherwise it retains the previous table position. This precisely explains Hold Shape During Cycle. The actual WT frame interpolation and phase-to-sample lookup are outside this body and remain unmapped.

Nitro port	Type
in	InputAudioPortType
table	InputAudioPortType
table_mod	InputAudioPortType
phase_in	InputAudioPortType
enable_latch	InputValuePortType
out	OutputAudioPortType
observer	OutputAudioPortType

Open questions #

• Measure interpolation across WT frames and samples, including Index boundaries and behavior with interpolation or wrapping options.
• Confirm the first-cycle latched Index, simultaneous Index change and phase wrap ordering, and stereo/polyphonic latch independence.
• Document accepted WT structures, table normalization, high-rate alias behavior, and the exact Don't Wrap Tables boundary rule.

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
• Bitwig Wavetable-LFO Modulator - Use Oscillator Shapes for Modulation

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