The three concerto transcribed from Vivaldi by J.S.Bach contain some indications on the distribution of the manuals, together with a numbers of sugestions as regards registers. Comparing the organs available to Bach at Weimar with the indications of the composer for the performance of his organ concertos, it can be seen, that none of these instruments was in the possession of all the prescribed manuals and registers. The new organ of the Municipal Church of Zofingen, Switzerland, satisfies all these requirements. And the reeds of North German construction complete this picture of an ideal organ - an organ of the kind that Bach envisaged for these brillant compositions.
Rudolf Scheidegger