Original title: SongCraft: Unified Song Generation and Editing with Reconstructive Learning
Haohe Liu, Varun Nagaraja, Gael Le Lan, Xinhao Mei +4 · September 2026
Computer models usually treat making new songs and editing existing ones as two separate jobs. Editing often relies on adding random noise and regenerating, or collecting matched pairs of songs. Researchers built a system called SongCraft to do both jobs at once. It learns by reconstructing audio from different controls. Giving it broad controls, like text descriptions and lyrics, lets it generate diverse songs. Giving it detailed controls for specific musical pieces lets it recreate the exact audio. To edit, users change just one piece while holding the rest steady. The team also aligned phonemes, the distinct speech sounds, with words, added beat controls, and organized the model's inner representations. SongCraft reached the lowest word error rate among tested baselines, kept competitive audio quality, and successfully edited lyrics, vocal melodies, beats, and singer identities.
You have a Lego castle you built from a picture—no instructions. Now you want to replace just the blue towers with red ones, without dismantling the walls or gates. Normally, to change one part you'd have to rebuild the whole thing or break other pieces. In this paper, the castle is a song: a model learns to rebuild it from different levels of detail. If you only tell it 'castle with towers', it builds freely. But if you specify every brick color and shape, it can then swap just the towers while keeping everything else intact.
Song editing today is clunky: you either re-record, use tools that damage audio, or need paired training data. This shows a single model can generate songs from scratch and let you change just the lyrics, tune, beat, or singer—without losing the rest. For musicians, that means faster iteration and cleaner edits; for listeners, songs tailored without losing their feel.
The abstract notes a trade-off between reconstruction quality and editability, implying that optimizing for one may hurt the other. It does not compare editing fidelity against dedicated editing baselines, does not evaluate on long-form or multi-instrument songs, and does not specify how well edits generalize to unseen genres or singing styles. The word error rate improvement is specific to the evaluated baselines; competitive audio quality is stated without rigorous listening tests.
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SongCraft: Unified Song Generation and Editing with Reconstructive Learning — Haohe Liu, Varun Nagaraja, Gael Le Lan et al.
Abstract licence: CC0
Explanation generated by Synthesis from the abstract — it is not the original paper. This is a preprint, so it hasn't necessarily been peer reviewed.