ChordWeaver

Product Introduction

1. Definition: ChordWeaver is a free, open-source desktop application for Windows that functions as an advanced music theory and composition tool. It is a generative AI music software that utilizes a genetic algorithm to solve complex voice-leading and harmonic progression problems.
2. Core Value Proposition: ChordWeaver exists to automate and teach the intricate rules of music composition, specifically voice leading and harmony, across different historical and stylistic genres. It transforms user input—chords, a melody, or a blank slate—into fully-realized, multi-voice musical pieces that adhere to strict contrapuntal rules, making advanced music theory accessible and practical.

Main Features

1. Three Core Composition Modes: The software operates via three distinct generative modes. The "Chords Mode" allows users to input a chord progression (in American jazz notation or via MusicXML import) and the algorithm distributes the notes optimally across voices. The "Progression Mode" generates a complete harmonic progression based on user-defined parameters (key, mode, start/end chords) before applying voice-leading. The "Melody Mode" lets users draw a melodic line, and the software harmonizes it by finding supporting chords.
2. Stylistic Rule Engines: ChordWeaver incorporates distinct, configurable rule sets for different musical genres. The "Baroque" style enforces Common Practice period counterpoint (e.g., prohibiting parallel fifths/octaves). The "Gregorian" style focuses on modal writing and permits parallel organum. The "Jazz" style prioritizes smooth voice-leading of guide tones (3rds and 7ths) and extended harmonies. Users can adjust the weight of these rules.
3. Integrated Analysis & Educational Tools: Beyond generation, the software includes a powerful "Analyzer" tool that deconstructs existing MusicXML scores, identifying chord inversions, harmonic functions, cadences, and voice-leading errors. The "Theory Book" is a dynamic educational component that unlocks new chapters as users achieve specific compositional milestones (e.g., generating a deceptive cadence), gamifying music theory learning.
4. Technical Audio Synthesis & Export: It features a built-in harmonic spectrum synthesizer ("Experimenter") that generates and exports .wav files as tuned, loop-ready sampler instruments. All musical output can be exported as standard MIDI or MusicXML files for use in DAWs or notation software like MuseScore, Sibelius, or Finale.

Problems Solved

1. Pain Point: Manually composing idiomatic multi-voice music (e.g., for choir or string quartet) requires deep knowledge of complex, genre-specific rules. This creates a high barrier to entry for students, hobbyists, and even experienced composers seeking efficiency.
2. Target Audience: Music composition students, hobbyist composers, songwriters seeking sophisticated arrangements, educators teaching counterpoint and harmony, and choral or ensemble arrangers.
3. Use Cases: A student struggling with Baroque counterpoint homework can input a figured bass and generate multiple correct voice-leading solutions. A songwriter with a melody can quickly generate professional-sounding chord progressions and harmonizations in a chosen style. A composer can use the analyzer to check an existing score for hidden parallel fifths or to understand the harmonic function of a complex passage.

Unique Advantages

1. Differentiation: Unlike standard DAWs or notation software that merely record or playback notes, ChordWeaver actively composes and critiques based on algorithmic rules. Unlike other "AI music generators," it is deterministic, rule-based, and focused on educational transparency rather than opaque, black-box generation.
2. Key Innovation: Its core is a unified evaluation engine. The same code that powers the genetic algorithm for generation also powers the analytical tool for critique, ensuring absolute consistency—the analyzer cannot approve what the generator would forbid. The "Story Mode," which unlocks secret content through normal use, is a novel gamification approach for creative software.

Frequently Asked Questions (FAQ)

1. Is ChordWeaver really free, and what does open-source mean? Yes, ChordWeaver is completely free (gratis) software released under the permissive MIT license. "Open-source" means its full Python source code is publicly available on GitHub, allowing users to inspect, modify, and distribute it.
2. What are the system requirements for ChordWeaver? ChordWeaver is a standalone Windows (64-bit) executable. It requires no installation, no separate Python installation, and is portable (can run from a USB drive). The download is approximately 28 MB.
3. Can ChordWeaver export files for other music software? Yes, ChordWeaver exports compositions in two universal formats: MusicXML (for notation software like MuseScore, Sibelius) and Standard MIDI Files (for DAWs like Ableton Live, FL Studio, or Logic Pro).
4. How does the genetic algorithm in ChordWeaver work? The algorithm treats a specific voicing of a chord progression as a "genome." It creates a population of random voicings, evaluates them against the selected stylistic rule set (assigning penalty scores for errors), and "breeds" the best ones over many generations to evolve towards an optimal solution, presenting the top three results.
5. Does ChordWeaver work for genres beyond Classical and Jazz? Its current rule sets are explicitly modeled for Baroque, Gregorian, and Jazz harmony. While its framework is flexible, creating a new genre (e.g., modern pop, metal) would require defining a new set of rules within its codebase, a task for advanced users.