audio2guitar vs Omnizart

audio2guitar is a web app that converts uploaded audio into guitar tablature, chord diagrams and lyrics synchronized to the tabs. Its process isolates guitar, detects notes and chords, maps notes to fret positions and creates the notation. Free users upload MP3 files; Pro also accepts WAV, FLAC, M4A, OGG and AAC. The maker says it detects more than 170 chord types and annotates hammer-ons, pull-offs, slides, bends, vibrato and palm mutes. Pro adds MIDI and PDF export, separated vocals, bass, drums, guitar and piano stems as MP3, per-stem MIDI, and playback from 25% to 100% speed while preserving sync and pitch. A valid Google account is required. The homepage reports 97.8% string-assignment accuracy on GuitarSet and says clean recordings with prominent guitar work best. Most songs process in 3–6 minutes. Plans include Free at free, Pro Monthly at $8.99 a month, Pro Annual at $59.99 a year, and One-time at $9.99, paid once.

Omnizart is a free Python library for transcribing polyphonic music into pitched instruments, vocal melody, chords, drum events, and beats. Pre-trained checkpoints allow transcription without first training a model. The project also documents dataset downloads, feature preprocessing, model training, transcription, and sonification, with MIDI, CSV, and text output formats. It lists separate applications for music, drums, vocals, vocal contours, chords, and beats, along with chord detection, MIDI export, and stem separation. Installation options include pip, Docker, and Conda, and a command-line interface is provided. Documentation links to a Colab notebook and a Replicate web demo. Omnizart supports Linux, Windows, macOS, and self-hosted setups, but is incompatible with ARM-based macOS because of underlying dependencies. The package requires Python 3.8 or later and below 3.15. Drum checkpoints can be used for transcription, though the drum model has an unresolved issue that prevents loss convergence when training from scratch. It is MIT-licensed and offers GitHub Issues for installation, compatibility, and usage problems.