Downspout Algorithms

This note summarizes the main generation and processing methods used by the current Downspout plugins.

MIDI generators

• BassGen: transport-synced monophonic bass generation with style and scale vocabularies, rhythm regeneration, color-driven harmonic tension, MIDI follow/dodge behavior, Jazz-specific ii-V-I / turnaround targeting, and Fugue subject/answer bass behavior.
• DrumGen: transport-aware drum pattern generation with fill logic, style modes, genre vocabularies, pattern mutation around the current cycle, and a sparse Fugue pulse mode.
• MelGen: phrase-aware monophonic melody generation with contour, call and answer, structure, range, color, follow controls, and a high-structure Fugue-friendly subject/dominant-answer region.
• Ground: longer-horizon bass generation that plans phrase roles, movement, cadences, pedal phrases, color, and high-sequence subject/answer forms across sections rather than just local bars.
• Cadence: learned harmony generation from captured MIDI, with scale-aware voicing, chord-size modes, comp scheduling, variation, arpeggiated playback phrasing, Jazz ii-V-I bias, and high-color circle-of-fifths/suspended dominant support.
• Counterpointer: learns an incoming MIDI line and answers it with a monophonic complementary line that can lean into contrary motion, chromatic color, rhythmic response, and strict dominant-answer imitation.
• Lifeform: Conway’s Game of Life drives the MIDI output, advancing the grid one beat at a time and turning active cells into musical events.
• Luma: an 8x8 Launchpad grid drives a small set of musical agents where cells can act as bass, chord, melody, or drum sources.

Audio effects

• P-Mix: transport-aware probabilistic audio gating and blending with fades.
• E-Mix: Euclidean stereo gating that carves audio into repeating patterns using density, block, and fade controls.
• Rift: short-buffer capture and disruption with repeat, reverse, skip, smear, and pitch-slip actions.
• PaunchLad: a dub-style performance effect built around delay throws, sirens, spring splashes, dropouts, and rhythmic chops.

MIDI effects

• M-Mix: MIDI gating that combines transport-locked probability decisions with Euclidean block patterns.
• Gremlin Driver: modulation and action sequencing that emits CC movement, action notes, and patch-randomization bursts for Gremlin.
• Cadence: input-aware MIDI harmonizing and comping that learns a cycle, rebuilds voicings from captured material, and can thin or break chords with Spread and Arpeggio.

Instruments

• Basilico: a monophonic bass synth with glide, accent, filter, body, and drive shaping for upright, electric, dub, acid, and industrial tones.
• DrumKit: a triggered drum synthesizer with a fixed MIDI map, voice controls, and mixer-style mute strips.
• Floozy: an 8-voice hybrid synth combining distortion, physical-model-style excitation, feedback, filtering, modulation, and reverb.
• Gremlin: a chaotic glitch synth with sound modes, scenes, fader macros, performance actions, hold pads, and MIDI LED feedback.

How the site treats these methods

The plugin cards on the GitHub Pages site stay short on purpose. This page is the place to read the implementation patterns in one place when comparing generators, effects, and instruments.