I don't know if music in a new language works so well. Lots of songs have, like, "forced" slang or even changes in pronunciation or syllable stress to meet the constraints of the lyrics. In my country I see lots of people that only listen to music in English but don't have any grasp of it.
Instead, I would go with cartoons or children/preteen's shows first. In adult shows, even when not R-rated, characters usually speak way too fast, or, what is most common, the voices are not mixed very clearly, unlike cartoons.
What worked for me best (for English) was watching Disney movies, the same ones I watched in Spanish.
> She was great, 60 years old at the time and had us repeat the lyrics of Rammstein songs in class, her favorite band
This is hilarious, like "Now, kids, repeat after me, 'te quiero puta'"
> Instead, I would go with cartoons or children/preteen's shows first.
Just be careful. I was watching Dora en Francais, and whenever Monsieur Diego was talking, I was like, woah, I understand it now, but that's cause he was speaking english.
Regarding the Cartoons totally, way easier to understand them because they speaking slow. I'm learning German right now the same way
> Lots of songs have, like, "forced" slang or even changes in pronunciation or syllable stress to meet the constraints of the lyrics.
I agree. I’d be wary of this as a beginner, but when you get more advanced, it becomes helpful in untangling your hearing from the isolated, intentionally clean and slowed-down setting of a class.
People don’t actually talk like that. Some slur their speech, others have a heavy accent, and others just place emphasis wherever they feel like it. Some kinds of music* work well for giving you an ear for the changes that matter (And even with all the changes, natives still are able to understand most music, so it is a skill to learn).
* I love me some guturals in my music, but it's probably not the best way to train your ear for every day conversation