== Crossposted from Music.SE as the question was deemed more appropriate for this site by a user with lots of rep ==
Consider this Harnoncourt recording of: Johannespassion, BWV 245, Part 1: "Herr, unser Herrscher". I can't figure out if the very low notes at the very beginning are played by a (contra)basoon or a contrabass (or both). I don't know how to figure this out since there's is no guarantee that Harnoncourt adhered to the instrumentation of any sheet music of this piece that I can find. To me, the first note really sounds like a string being played, while the other ones could also be a woodwind instrument playing.
I'd be grateful for anyone with a more precise ear than me and even more for someone with a source for the correct answer of this question.