There are several things involved, copyright of the song by the composer, copyright of the particular performance by the performer, and mechanical reproduction rights of the recording. The musician may be able to grant you rights to the performance and recording, but not to the composition.

It may also depend on what you’re doing with the model. If you analyse the composition, and create new songs in the style of the composer, that’s more likely to infringe their copyright, than if you’re analysing the performance style of the musician, and creating renditions of other songs in the musician’s style. If you’re doing scientific research, it’s likely to enjoy a fair use exception. If you’re monetizing it, and it takes away income from the composer, then not. Even if you’re not monetizing it, there’s still a possibility to get a “cease and desist” order from the copyright holder if you don’t have a fair use exemption. It’s complex, and depends on the laws, court decisions, and international treaties. You won’t likely get a reliable explanation from Reddit armchair copyright experts, including me.

The legality of AI and music is still up in the air to some extent. We know from the Heart on my Sleeve track that it’s not just a fair-use free-for-all as some Redditors here suggest.

I doubt you’ll find 12 different emotions on Reddit. I think everything can fit into:

1. sarcasm
2. rage
3. polemic rage
4. bewilderment
5. jocularity
6. serious

I might have missed one or two, but I’m sure there aren’t 12.

How is it all that different from writing a self-help book though, in a legal sense? Why is there any bigger liability and ethical issue? There are millions of such books and articles published, full of all sorts of nonsense. A mentally unstable person might follow one and experience a bad outcome. No reason to stop releasing books though. A simple disclaimer seems to suffice. I understand that the experience of an LLM is not the same thing as reading a book, but it is in a sense just indexing and summarizing many texts in an interactive way. Why do you think it would be treated differently under the law, are there specific laws that apply to LLMs but not to books?