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No. 16 Extension
Extension ranks are commonly found in pedal divisions in the classical pipe organ. 32’ to 4’ can be taken from a single rank without the problem of missing notes. St James Wufstan Way and the Congregational Chapel at Fordham Cambridgeshire have examples of extension on manuals also by Johnsons.
The ultimate use of extension was carried out in cinema organs, such as the Wurlitzer pictured.
There are 32 speaking stops on the console, but just 5 ranks of pipes -
The Vox Humana, by the way, has such short resonators that it ought to be called Vox Oviana for its curious bleating sound.