Der du bist drei in Einigkeit

Christian David Graff worked as organist at Kirche St. Ulrich und Levin in Magdeburg from 1719 until his death in 1774. He was a pupil of Johann Bernhard Bach (a cousin of J.S. Bach). In the past Graff was considered a pupil from J.S. Bach, but that isn't true, probably the cause of a confusion between J.S. and J.B. Bach.

Christian David Graff played at a Schnitger organ in Magdeburg. So the beautiful sample set of the Schnitger organ in Steinkirchen was an obvious choice.

Edo played this fine chorale prelude too, on the Poblet sample set: https://www.contrebombarde.com/concerthall/music/40889