Contrapunctus vs Interactive Music Theory Lab

Contrapunctus is a free web platform for music theory, composition, and counterpoint study. Its real-time editor shows Roman-numeral and chord analysis while users write, and identifies part-writing errors and non-chord tones. Compositions can use multiple voices, major, minor, or modal contexts, and sampled-instrument playback. The platform includes an interactive edition of Fux’s Gradus ad Parnassum, with species-counterpoint lessons, an AI tutor, and English and Latin text. Community members can create and solve exercises, share solutions, vote, and earn points toward a 15-rank ladder. Educators can create classes, assign lessons, review submissions, and track scores and class averages in a gradebook. Accounts use email or Google, with projects and activity synchronized across devices. Plain and compressed MusicXML can be imported, but MusicXML or MIDI export is not yet shipped. Some imported details may be simplified or dropped, and tutor free-form questions are limited to 25 per account per rolling hour.

Interactive Music Theory Lab is a free web app for learning and applying music theory. Chord Lab offers an interactive chord builder, chord library, piano keyboard, staff notation, voicings, and inversions. Scale Explorer covers more than 100 scales and maps their patterns on piano and fretboard. Theory Academy provides interactive lessons, guided tutorials, exercises, and subjects ranging from intervals to voice leading. Composition Studio lets users arrange progressions and song sections by drag and drop, receive theory-based suggestions, and export MIDI or PDF. The interface also lists MIDI and MusicXML import and export, along with PDF and audio export. Users can upload MP3, WAV, OGG, M4A, or FLAC files for chord-progression detection; clear recordings work better than complex mixes. The service requires no account and includes progress tracking. It offers guidance rather than writing songs for users, and the maker notes that bugs exist.