I’ve combined these headphones with earplugs for a plane trip. Engine roar overpowers the sound for bone conducting headphones the same way it does for earbuds or headphones that don’t isolate. You might still need to crank the volume up, though. Planes are loud. No issue of other people overhearing it at that point though.
This is a really interesting question. If I were a researcher, I’d try to go chase this topic, since it seems to be fairly quantifiable.
Like Mudskipper, I can replay music in my head but it has a few caveats: I don’t really process the instruments… I remember the pitch/volume/etc but primarily of vocals. I also replay with the original singer’s voice and not my own. Replaying a few songs in my head now and I can’t even focus on the instruments if there were vocals unless they are critical to how the song works, like a bass drop. If I try to replay music that is instrumental, I get verbal recreations, like someone performing the song acapella. If i focus hard, I can hear instruments instead, but that requires thinking about it. This matches how I ‘sing along’ with instrumental pieces in otherwise verbal songs. It might just be that the backing music isn’t retained, so I can remember the melody, but not, say, a bass line unless the bass is being highlighted.
Are there people who CAN’T replay music in their heads? Are they immune to ‘ear-worms’ or do they just perceive it differently?