Gottfried Frietzsch and the large organ in Hamburg’s St.-Katharinen. The number of manuals, their compass, and their subsemitonesby Ibo Ortgies | Het ORGEL | Year 116 | (2020) | Issue 2
In 1629 Gottfried Frietzsch (1578-1638), court organ builder in Saxony, began in Hamburg on the last important phase of his life’s work: he had built there his first organ in the monastery church of St.-Maria-Magdalena, providing the instrument with subsemitones. Subsemitones are additional sharp keys by which the usual number of 12 tones per octave is increased. They enlarge the number of usable keys in meantone tuning, keeping the purity of the thirds in major chords. The need for subsemitones came primarily from the necessity of transposition when accompanying ensembles. Organs with subsemitones usually had one or two such keys per octave in the middle octaves, sometimes three or even four, though this was rare. In this article the author discusses the work of Frietzsch on the famous organ in St.-Katharinen in Hamburg, studying the number of manuals, their compass, and the presence of subsemitones.