I was just listening to some live Alan Parsons Project stuff (surprisingly good, btw) and I know Alan Parsons was the engineer on Pink Floyd’s Dark Side of the Moon (which sold a zillion copies).
Would he get royalties or would he have gotten a flat salary?
I don’t know what kind of contract Alan Parsons might have signed, but if you’re just a basic knob twister at an ordinary recording session, you get a flat salary and go on to your next session.
Big-name and sought out producers (for ex. Rick Rubin, Dr. Dre, etc) often accept points on a project in lieu of a flat fee.
With engineers, it’s probably less likely, but not unheard - an engineer like Eddie Kramer (Jimi Hendrix) or George Martin (Beatles) would be a lot more likely to get points than JoeBob Sixpack in a mid-sized project studio. (Note: I have no idea if George Martin or Eddie Kramer actually did receive a piece of the action, they’re jsut well-known examples and I wouldn’t be surprised in the least if they did)
The most likely non-musician to receive royalties on a project is the lyricist, in a collaborative writing scenario - but that is publishing royalties (paid to the composers of the work) rather than mechanical royalties, paid to the performers.
The engineer of an album made by a band he’s not part of is highly unlikely to get royalties, unless he’s so powerful or so high-profile that he can demand them.
Even musicians who aren’t members of a group don’t get royalties- if they did, the Funk Brothers (the session musicians who played on all the Motown smash hits of the 60’s) would be gazillionaires, instead of ordinary middle-class retirees.
The revenge of the engineers came when the advent of electronic dance pop made it possible to engineer a hit record without any real musicians! Over the past few decades, a lot of big dance hits have been engineered more than played or sung, and a lot of dance pop “groups” have been non-existent fronts.