I think it was a 16 track, too
At least that's what I heard. It was probably two 16-tracks synched. I could be wrong, though. The story about the tape going transparent is apparently true. After passing over the heads so many times during tracking, some oxide eventually flakes off. I think that this was also the case for the Queen II album, which has an amazing amount of vocal and guitar overdubs as well. Regarding who sings in "Bohemian Rhapsody," it's quite obviously all Freddy in the a capella intro, but Freddie, Brian, and Roger do the operatic vocals in the middle in the places where it's all massed and huge. Some of those parts are all Freddie as well (e.g. "Magnifico-o-o-o-o!," "Never, never, never, let me go - Oh-oh-oh-oh!") RTB also believed in recording WITH EFFECTS; i.e., he recorded the reverb on the vocals and whatnot while they were tracking instead of adding it during the mixing stage. That of course required quite a bit of pre-planning, but then again, it made mixing a little easier.
BTW, John Deacon never sang on any Queen album.
Another trick that Roy Thomas Baker used when recording Queen, Starcastle, the Cars, Journey, etc., was to hit the tape with as hot a signal as possible in order to get that loud but compressed sound. He did that with vocals as well, which helps make them sound bigger. Think of how the a capella vocals sound at the beginning of "Bicycle Race," for example: really loud and in-your-face, even a bit distorted. You'll notice that on a lot of recordings RTB's produced, the drums actually distort quite a bit. Listen to the toms on "Father to Son" on Queen II. (In fact, nearly every song on that album has distorted drums!) I remember reading that he'd have the engineers push the faders up all the way when they were tracking, and the VU meters would always be in the red. The idea was to get a recording that in the end sounded LOUD. That way, it would have more impact when played on the radio. This same mentality exists in the world of mastering, though these days it's been taken to ridiculous proportions.
(I got most of this from an interview w/Roy Thomas Baker from the website artistpro.com)
Bruce in Korea