Kuaffmann's chorale prelude to "Wo Gott zum Haus nicht gibt sein Gunst" is a nice example of Trio writing, with the chorale melody in the bass voice. The other two voices introduce each phrase of the chorale melody with short fore imitations. Kauffmann prescribes a Principal for both upper voices, so they are a bit difficult to discern individually while listening to the piece.
The recording was done with the Hauptwerk software and the sampleset, made by Voxus, of the Müller organ in the Sint Bavokerk, Haarlem (http://www.voxusorgans.com/en/product/haarlem).
Score available: http://partitura.org/index.php/georg-friedrich-kauffmann-wo-gott-zum-haus-nicht-gibt-sein-gunst