Grain Filter

Overview

The Grain Filter gives every grain its own multi-mode filter, with independent modulation and drive. Because each grain is filtered on its own, tone and texture shift and evolve from grain to grain in ways a single filter never could.

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1. Filter Mode and display

Grain Filter Mode

Select the filter type applied to each grain.

• Lowpass. Passes frequencies below the cutoff. Includes Drive for saturated, aggressive filter sweeps.

• Highpass. Passes frequencies above the cutoff. Includes Drive for added harmonic character.

• Bandpass. Focuses on frequencies around the cutoff. Includes Drive, making it ideal for vocal-like and resonant textures.

• Notch. Removes frequencies around the cutoff. Includes Drive for hollow, phasey movement.

• Morph. Smoothly transitions between Lowpass, Bandpass, Highpass, and Notch using the Morph control.

• Vowel. Three formant bands create a vowel-like resonance. Cutoff sets the voice's base frequency, and Morph selects the vowel.

• Comb. A resonant comb filter with Damping control. When Scale is enabled, it functions as a tuned resonator.

• Flange. A short modulated comb filter with Damping, creating metallic resonances and per-grain flanging effects. Can also be tuned with Scale.

• Modal. Four bands tuned to the resonant modes of a struck object. Cutoff sets the fundamental, Morph spreads the modes apart and is tuned at either end of its travel and inharmonic between them, and Resonance sets how tightly each mode rings.

• Phaser. A multi-stage phaser where Morph controls the spacing of notches and peaks across the frequency spectrum.

• Allpass. A phase-shifting allpass filter chain. Morph spreads the phase stages to create diffuse, smeared coloration.

• Reducer. Combines sample rate reduction and bit depth reduction for lo-fi textures. Cutoff controls the sample rate, Smooth softens reconstruction artifacts, and Bits adjusts bit depth.

2. Filter Controls

Scale

Quantizes the filter cutoff to the currently selected musical scale.

This allows resonant filters, comb filters, and flangers to function as tuned resonators for harmonic filtering effects.

Scale does not affect the filter's internal modulation unless Random modulation is enabled.

Cutoff

Set the cutoff frequency of the per-grain filter.

With the Scale button above the knob enabled, the cutoff snaps to notes in the active scale, turning resonant filter modes into tuned, in-key resonators.

Random

Randomizes each grain's filter cutoff instead of applying a continuous modulation sweep.

This is ideal for introducing variation and unpredictability to dense granular textures.

When Scale is enabled, randomized cutoff values are quantized to the active musical scale.

Mod Depth

Controls how far the filter cutoff moves during each grain's lifetime.

Every grain modulates its filter independently, creating unique movement across the texture. Negative values reverse the modulation direction.

Enable Random to replace the sweep with a randomized cutoff offset for every grain.

Mod Rate

Controls how many modulation cycles occur during each grain's lifetime.

• 1. One complete filter sweep per grain.

• Higher values. Faster modulation, reaching audio-rate FM-style effects with shorter grain sizes.

This parameter has no effect when Random is enabled.

Resonance

Set the resonance of the per-grain filter.

Higher values sharpen the filter's resonant peaks, emphasizing those frequencies and introducing more ringing tones.

The exact character of the resonance depends on the active filter mode.

Drive

Adds per-grain saturation and harmonic distortion.

• 0%. Drive is disabled.

• Higher values. Produce increasingly aggressive soft clipping while preserving the detail and movement of individual grains.

Morph

Continuously adjust the per-grain filter's response. The exact movement depends on the active filter mode.

Modulate it for evolving tonal movement.

Damping

Available in Comb and Flange modes.

Reduces high frequencies in the feedback path, causing higher harmonics to decay faster than lower ones.

• 0%. Bright, metallic resonances with minimal damping.

• Higher values. Darker, shorter resonances that resemble muted strings or damped resonators.

Smooth

Available in Reducer mode.

Applies smoothing between sample rate reduction steps.

• 0%: Raw, stair-stepped digital artifacts.

• Higher values: Softer aliasing and a smoother, lowpass-like character.

Bits

Available in Reducer mode.

Sets the bit depth of the reducer.

• 16 bits. Bit reduction is bypassed.

• Lower values. Introduce quantization noise and classic digital crunch.

Mix

Blends the filtered and unfiltered signal for each grain.

• 0%. Dry signal only.

• 100%. Fully filtered signal.

Grain Filter Bypass

Enables or disables the entire per-grain filter section.