alda-lang/alda
Alda
Alda is a text-based music programming language and command-line tool for composing, playing, and live-coding musical scores. It functions as a MIDI composition engine that renders plain-text scores into audio output, and as a live coding environment where code entered in a read-eval-print loop produces real-time playback without restarting the interpreter.
The system distinguishes itself through an event-driven playback engine that schedules timed note events, an instrument-attribute inheritance model that cascades properties like volume and tempo from global defaults to individual parts, and marker-based synchronization that aligns multiple instrument parts by naming time points. It also supports octave-shift operator notation for pitch changes, variable-based pattern reuse for storing and transforming musical motifs, and MIDI-based audio rendering using standard instrument sound sets.
The platform covers the full scope of music composition through text-based score authoring, including note pitch and duration specification, chord and polyphonic voice construction, key signature application, multi-voice score structuring, and per-instrument attribute adjustment for tempo, dynamics, and articulation. It enables algorithmic music generation, reusable pattern definition, and file-based or command-line score playback.
Features
- Algorithmic Music Composition - Creates scores programmatically by treating music as data for generative or procedural composition.
- Text-Based Score Programming - Writes musical scores using a text-based programming language for version control and repeatable playback.
- Multi-Voice Score Organization - Organizes music into separate voices and parts that play simultaneously with independent settings.
- MIDI Music Composition Tools - Renders text scores to MIDI output using standard instrument sets for playback or export.
- Command-Line Music Players - Executes composed scores directly in the terminal to produce audio output without a graphical interface.
- File-Based Score Players - Runs text files containing music code to hear the full composition performed from the command line.
- Interactive REPLs - Provides an interactive REPL for entering music code and hearing results in real time without leaving the editor.
- Instrument Playback Controls - Modifies per-instrument properties like volume, quantization, and tempo to shape individual part sounds.
- Marker-Based Synchronization - Aligns multiple instrument parts by naming time points and jumping between them for synchronized playback.
- Multi-Instrument Score Synchronizers - Writes separate instrument parts with independent attributes and markers to coordinate simultaneous playback.
- Instrument Track Assignments - Assigns specific synthesizer voices to individual audio tracks for simultaneous playback.
- Live Coding Music Performance - Enables live coding music by entering code in a read-eval-print loop and hearing results in real time.
- Macro Language Music Notation - Provides a text-based language for composing and playing back musical scores from the command line or REPL.
- Text-Based Score Editors - Composes music as plain text with syntax for notes, rests, chords, and instruments for version control and repeatable playback.
- Fixed Note Durations - Specifies note lengths as numbers and uses rests to create silence between notes in a score.
- Text-Based Score Editors - Represents musical scores as plain text files parsed into an abstract syntax tree for interpretation and playback.
- Key Signature Definitions - Sets major, minor, modal, or custom key signatures that affect pitch interpretation across the score.
- Note Definition with Defaults - Defines notes by letter name, octave, accidental, and length with defaults that persist until changed.
- Octave Shift Operators - Changes note pitch by shifting octaves up or down using angle bracket operators that persist until reset.
- Pitch and Duration Specification - Specifies notes by octave, accidental, and length using standard or custom time values.
- Chord and Voice Construction - Constructs chords and polyphonic voices by playing multiple notes simultaneously on one instrument.
- Reusable Musical Patterns - Stores note sequences, chords, or motifs in variables and repeats them with or without variations.
- Playback Speed and Volume Controls - Adjusts playback speed and volume globally or per instrument part using dynamic markings.
- MIDI-to-Audio Synthesizers - Renders compositions to audio by generating MIDI events and sending them to a software synthesizer.
- MIDI Output Controls - Renders compositions to MIDI with standard sound sets and adjusts per-instrument properties like volume and tempo.
- Music Score Marker Synchronizers - Aligns multiple instrument parts by naming time points and jumping between them for synchronized playback.
- Multi-Part Score Coordination - Coordinates multiple instrument parts to play simultaneously with global attributes and markers.
- Interactive Read-Eval-Print Loops - Provides an interactive read-eval-print loop for real-time music code evaluation and playback.
- Domain Specific Languages - Provides a domain-specific language for writing musical scores as text and playing them back from the command line.
- Music Playback Schedulers - Schedules timed note events from parsed scores into real-time audio output for playback.
- Tempo and Dynamics Defaults - Applies global tempo and dynamics settings that affect all instruments simultaneously in a score.
- Music Instrument Attribute Cascades - Cascades per-instrument properties like volume and tempo from global defaults to individual parts.
- Music Pattern Variables - Stores reusable musical patterns in named variables for reference and transformation within scores.
- Articulation Percentage Controls - Adjusts note length as a percentage of its duration to create staccato or legato articulation effects.
- Music Octave Shift Operators - Changes note pitch by shifting octaves up or down using persistent angle bracket operators.
- Go Projects - Listed in the “Go Projects” section of the Awesome For Beginners awesome list.
- Music Programming - Music programming language designed for musicians.
- Audio And Music - Music programming language for Clojure.
