Without an agreement with the author, you cannot make copies of a copy you have bought legally, for he (or more exactly, the copyright-holders) is the only one allowed to make further copies.
Since this would make playing CDs on a computer impossible laws provide exceptions for the purposes of playing your legally bought representation (copies are made in cache memory, buffers etc...)
Other exceptions may be given (fair use doctrine, explicit mentions in other countries) letting you arrange a performance of the work (playing the CD) inside your private circle. (This would be impossible to enforce against)
So it stands to logic that if you have bought say, a vinyl of a particular work, you do not have a right to obtain counterfeit copies made of other representations (of the same work) as CDs or digital files.
Can an older guy to download via torrent all of the music from old vinyl records he has in the closet? Considering economic conditions, receiving 9.99 for every crappy cd I bought as a teen would be nice.
Could one sell back to the record industry for the "value" of the digital rights?
I don't really agree with this, but one could apply this logic to vhs/dvds, books.