The choral prelude on "Nun komm der heiden Heiland" by Telemann is a bit strange. While playing it I can’t stop feeling that the piece could better be sung then played on an organ. Yet it would be very difficult to sing. Telemann’s writes some very strict counterpoint in this piece, resulting in some harsh dissonants. The stretto starting in bar 18 starts each entry of the subject one step higher on the scale. The result is three bars full of major and minor seconds and sevenths. It is almost a miracle the music doesn’t fall to pieces.