Marpurg's prelude to "Wenn Christus seine Kriche schützt" has the choral melody in the pedals. It has a march-like rythm, a playing indication "Heroic" and together with the melody in the pedals that begs for a plenum registration. Perhaps that registration choice is a bit too obvious, nevertheless it works beautifully in this piece.
Somehow I did not mount the camera properly (again), so in the second half of the video you don't see my hands any more, only my head and shoulders. Since I recorded this video I invested in some new gear, so I hope it won't happen in newer videos.
The recording was done with the Hauptwerk software and the sampleset, made by Sonus Paradisi, of the Schnittger organ in the St. Martini-kerk, Groningen (https://www.sonusparadisi.cz/en/organs/netherlands/groningen-st-martini.html).
Score available here: http://partitura.org/index.php/friedrich-wilhelm-marpurg-wenn-christus-seine-kirche-schutzt