Howl

A damped sine wavefolder that brings successive input regions into alternating, loud focus.

What it does #

Howl drives the signal through a sine-based folder, then reduces the amplitude of increasingly distant folds with a reciprocal window. The result cycles through emphasized regions while remaining bounded as Drive grows.

Controls and ports #

Signal In is multiplied by Drive, HQ selects the high-order filtered/antiderivative path, and Signal Out returns the windowed sine-fold result.

Practical uses #

• Sweep Drive on a sustained tone to move different waveform regions into focus.
• Use it for aggressive vocal, bass, and percussion coloration with a bounded output.
• Mix it in parallel when the full fold pattern removes too much of the original fundamental.

Things to know #

• Its static curve changes direction repeatedly because of the sine term.
• The reciprocal window makes folds farther from zero quieter rather than equally loud.
• The HQ path also applies four 18 kHz one-pole stages to the sine and window components.
• Different Drive values can cancel or restore the fundamental non-monotonically.

Technical details #

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

The exact grid/shaper/howl direct equation is out = sin((pi/2)*drive*x)/(1+|drive*x|). HQ evaluates the sine and reciprocal window with independent second-order ADAA objects, initializes their states on first use, low-passes each component through four stages at a nominal 18 kHz in the 4x domain, and multiplies them. This establishes a damped periodic folder with extra high-frequency control in HQ mode.

Nitro port	Type
x	InputAudioPortType
drive	InputAudioPortType
HQ	InputValuePortType
out	OutputAudioPortType

Open questions #

• Measure the HQ low-pass calibration, latency, magnitude change, and alias rejection across sample rates.
• Map visible Drive to fold count and quantify harmonic/fundamental cancellations.
• Confirm the apparently hardwired likelyHQ branch, UI switch behavior, stereo independence, and reset transient.

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

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