Update, 27 december 2018: This fugue turns out to have been composed by Johann Jacob Froberger. The letters “F.S.” are either an misattribution, they stand for something like “Froberger Scripsit” (Froberger has written), or they mean something else entirely.
Manuscript Am B 340 contains two fugues, that have the initials “F.S” written beneath the title. Presumably those are the initials of the original composer of this fugue. Alas, I have no idea who these initials belong to. The first fugue is available here. The second fugue is equally beautiful. A chromatic ascending theme leads in the course of the fugue to lots of tantalizing suspensions. I hope to find out one day who this “F.S.” was.
The recording was done on the sample set of the Bader-organ in the Walburgiskerk in Zutphen by Sonus Paradisi for Hauptwerk.
Froberger, Fuga d moll (FbWV 416)
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