User Guide

Quick Start

Get up and running with Formfactor in five steps:

1. Load Formfactor as a MIDI effect (or Instrument in Logic Pro)
2. Route MIDI to Formfactor from your keyboard or sequencer
3. Route Formfactor's MIDI output to a synthesizer or effect
4. Enable one or more CC output lanes
5. Play notes and watch CC values respond to your playing

What Formfactor Does

Formfactor sits between your MIDI source and your instruments. It passes through all incoming MIDI (notes, pitch bend, existing CCs) while generating additional CC messages based on analysis of your playing. Think of it as an intelligent MIDI processor that creates modulation from musical context.

Typical Use Cases

• Dynamic filter sweeps that respond to playing intensity
• Automatic expression that follows note density
• Rhythmic modulation via step sequencer
• Shaped LFO with 24 modulation shapes
• Hardware modulation for synths without built-in LFOs

Signal Flow

MIDI enters Formfactor from your DAW, where it is read across four dimensions. The original MIDI passes through unchanged while new CC messages are generated and merged into the output stream.

                            FORMFACTOR
        ┌───────────────────────────────────────────────────────────┐
        │                                                           │
        │  ┌──────────┐                                             │
        │  │  READER  │                                             │
        │  │          │                                             │
        │  │ Temporal │    ┌─────────────┐    ┌───────────┐         │
        │  │ Density  │───▶│ Sequencer + │───▶│   Merge   │         │
  DAW  ▶│  │ Velocity │    │ Shape LFO   │    │           │         │▶  DAW /
        │  │ Intensity│    └─────────────┘    │ Passthru  │         │   External
        │  └──────────┘           │           │     +     │         │
        │        ▲                │           │  New CCs  │         │
 MIDI   │        │                ▼           └─────┬─────┘         │   MIDI
  In    │        │         ┌───────────┐            │               │    Out
────────┤        └────────▶│  8 Lanes  │────────────┘               ├────────
        │   (notes, etc.)  │ CC 1, 11  │                            │
        │                  │ 74, 71... │                            │
        │                  └───────────┘                            │
        └───────────────────────────────────────────────────────────┘

Each lane can be configured independently:

• CC number and channel for output routing
• Step sequencer with configurable trigger source
• Shape LFO with depth, rate, and mode controls
• Mode mutes to select which analyses affect the lane

GUI Overview

Formfactor's interface is organized into four main sections. Understanding where everything lives will help you navigate quickly.

Global Controls

These parameters affect overall Formfactor behavior. The analysis parameters below are accessible in the READER panel.

Temporal Sensitivity (0-100%)

How quickly the Temporal Intelligence analysis responds to changes in playing. Higher values react faster to tempo variations; lower values provide more stable readings.

Density Window (50-2000 ms)

Time window for Event Density analysis. Shorter windows respond quickly to bursts of notes; longer windows average over more playing time.

Velocity Smoothing (0-100%)

Amount of smoothing applied to velocity tracking. At 0%, CC follows velocity changes immediately. At 100%, changes are heavily filtered for gradual transitions.

Intensity (0-127)

Initial energy level for the Intensity system. Higher values allow more sustained activity before energy depletion affects modulation.

CC Output Lanes

Formfactor provides 8 independent CC output lanes. Each lane generates a single CC message stream based on its configuration.

Default CC Assignments

Lanes start with commonly-used CC numbers:

• Lane 1: CC 1 (Mod Wheel)
• Lane 2: CC 11 (Expression)
• Lane 3: CC 74 (Filter Cutoff)
• Lane 4: CC 71 (Resonance)
• Lane 5: CC 73 (Attack Time)
• Lane 6: CC 72 (Release Time)
• Lane 7: CC 91 (Reverb Send)
• Lane 8: CC 93 (Chorus Send)

Change any lane's CC number to suit your target instrument.

Lane Selector

The numbered circles above the Factor display select and enable/disable lanes:

• Click: Select a lane for editing
• Double-click: Toggle lane enabled/disabled (mute)

Enabled lanes show green; disabled lanes show red. Disabled lanes don't output CC messages and consume no CPU.

Lane Parameters

Enable

Lane on/off state, controlled via the lane selector (double-click to toggle).

CC Number (0-127)

Which CC number this lane outputs. Standard assignments include 1 (Mod), 7 (Volume), 10 (Pan), 11 (Expression), 74 (Cutoff), 71 (Resonance).

Channel (1-16)

MIDI channel for CC output. Usually matches your instrument's receive channel.

Value (0-127)

Base CC value before analysis modulation. The final output combines this with the sequencer, LFO, and analysis results.

Step Sequencer

Each lane includes an 8-step sequencer that cycles through values based on a trigger source.

Trigger Sources

Step Values

Each step holds a value from 0-127. The sequencer outputs this value, which is then processed through the lane's modulation shape before combining with other modulation sources.

Sequencer Behavior

• Steps are numbered 1-8 and cycle continuously
• When a step advances, the output transitions smoothly to the new value using the lane's shape
• You can mute sequencer influence per-lane using Mode Mutes

Modulation Shapes

Formfactor includes 24 modulation shapes that define how the LFO sweeps through its cycle. Each shape has a distinct character, from smooth curves to chaotic patterns.

Shape Categories

The READER

The READER continuously observes incoming MIDI across four dimensions. Each dimension produces a value from 0-127 that can modulate CC output.

Temporal Intelligence

Tracks the timing relationships between notes. Detects whether you're playing steady rhythms, accelerating, decelerating, or with rubato expression.

• Steady playing: Mid-range values (~64)
• Accelerating: Rising values toward 127
• Decelerating: Falling values toward 0
• Rubato/irregular: Fluctuating values

Use for: Filter sweeps that follow phrasing, effects that intensify with faster playing.

Event Density

Measures how many notes occur within the Density Window. Sparse playing produces low values; dense chords or rapid passages produce high values.

• Single notes: Low values (0-30)
• Moderate activity: Mid values (40-80)
• Dense chords/runs: High values (90-127)

Use for: Reverb send that opens up on solo notes, distortion that increases with intensity.

Velocity & Expression

Follows the velocity of incoming notes with configurable smoothing. Provides direct mapping from playing dynamics to CC output.

• Soft playing: Low CC values
• Hard playing: High CC values
• Smoothing: Prevents jumpy transitions between different velocities

Use for: Expression (CC 11), filter cutoff, any parameter that should track dynamics directly.

Intensity

A "stamina" system that depletes with activity and regenerates during rests. Creates natural tension and release curves over longer phrases.

• Fresh/rested: High values (near Intensity setting)
• After sustained activity: Depleted values
• During rests: Gradual regeneration

Use for: Modulation that "tires out" during long solos, effects that build and release over phrases.

Mode Mutes

Each lane can selectively ignore READER modes. This lets you create lanes that respond only to specific aspects of your playing.

Per-Lane Mutes

• Temporal Mute: Ignores Temporal Intelligence
• Density Mute: Ignores Event Density
• Velocity Mute: Ignores Velocity & Expression
• Intensity Mute: Ignores Intensity
• Sequencer Mute: Ignores step sequencer values

Use Cases

• Pure velocity tracking: Mute all except Velocity
• Sequencer-only: Mute all READER modes, use only sequencer
• Density-driven reverb: Mute Temporal, Velocity, Intensity; use only Density
• Intensity-aware expression: Mute Temporal, Density; combine Velocity and Intensity

Shape LFO

Each lane includes a tempo-synced Shape LFO that blends with the step sequencer output. The LFO uses one of 24 modulation shapes to define its waveform character.

Depth (0-100%)

Controls the blend between sequencer output and Shape LFO output:

• 0%: Output equals the sequencer value only
• 100%: Output equals the Shape LFO value only
• In between: Linear blend of both sources

Rate

Tempo-synced LFO cycle period:

• 1/4 beat: Fastest — one cycle per quarter beat
• 1/2 beat: One cycle per half beat
• 1 bar: One cycle per bar (default)
• 2 bars: One cycle every two bars
• 4 bars: One cycle every four bars
• 8 bars: Slowest — one cycle every eight bars

LFO Modes

Presets

Browsing Presets

The preset dropdown organizes configurations by use case. Click any preset name to load it instantly.

Factory Preset Categories

User Presets

Save your own configurations using your DAW's preset management or Formfactor's built-in preset system.

Preset Storage Location:

• macOS: ~/Library/Application Support/Aftertone & Signal/Formfactor/Presets/
• Windows: %APPDATA%/Aftertone & Signal/Formfactor/Presets/
• Linux: ~/.config/aftertone-and-signal/formfactor/presets/

MIDI Routing

Formfactor needs MIDI input to analyze and MIDI output to send its generated CCs.

Input Requirements

• Note-on/off messages for analysis
• Velocity values for Velocity & Expression mode
• Transport position for tempo-synced triggers

Output Behavior

• Pass-through: All incoming MIDI is passed unchanged
• Generated CCs: New CC messages are added to the stream
• No conflicts: If your input already contains CC 74, Formfactor's CC 74 output will interleave (consider using different CC numbers)

DAW-Specific Routing

Automation & Hardware Control

All Formfactor parameters are exposed for DAW automation and MIDI mapping.

Useful Parameters to Automate

• Active Lanes: Bring lanes in/out during a song
• Lane Enable: Toggle specific lanes
• Lane CC Number: Change target parameter mid-song
• Sequencer Steps: Create evolving patterns
• Shape Selection: Different shapes for different sections
• LFO Depth/Rate: Build intensity over time

Hardware Control

Map physical knobs to Formfactor's parameters using your DAW's MIDI learn feature. Particularly useful mappings:

• LFO Depth on a knob for performance control
• Density Window to adjust response character
• Lane base Value for manual CC override

Tips & Techniques

Parameter Reference

Analysis Parameters

Lane Parameters (per lane)

Formfactor v0.1.0
Aftertone & Signal
aftertone.co