St Mary and St Nicholas
with All Saints, Leatherhead
The 1766 Thomas Parker organ
Progress Report 4,
September 2007
Restoration & Assembly work
all images by permission of
Goetze & Gwynn unless otherwise stated
Casework
The casework has been completed and the final toning and
finishing is almost ready.
There is a division between the main front case and the rear
case, but it was decided to keep the colouring consistent since a
major viewing angle will be from the chancel/choir stalls, the
treble side being more visible than the organ front. The case
back, too, will form a passage to the vestry, so is also coloured
to match the rest.
The original keyboard provided a starting point for the staining scheme. Although the main part of the keyboard which is visible is mahogany, the top rail is oak which is now fairly dark. Reference was also made to some of the oak organ cases of the mid eighteenth century, such as St Margaret Pattens (City of London). Finally, the woodwork of the church was taken into account.
Wind
The wind system is based closely on that at Great
Packington, but has been assembled so that it is possible to blow
by hand as well as with the electric blower. When the blower is
switched on, a simple mechanical linkage allows either bellows to
inflate until the curtain valve cuts off the blower wind. The
hand pumping has been made so that the levers which protrude
through the treble side doors can easily be removed and stored
inside the case when not in use.
Assembly and voicing
With the keyboards installed, the rest of the key action
was assembled and tested. The touch weight of the Great keys was
found to be a little heavier than we thought it should have been,
and the pallet springs made a little lighter. There is a
noticeable amount of pluck towards the bass end of the Great
keyboard. This is due to the rather wide channels, and to be
expected.
The flue voicing has followed the example of Great Packington, supplemented by information documented during the restoration work carried out on other Parker organs. Most of the Parker pipes at Leatherhead have had extra voicing work carried out over a number of rebuilding occasions, and choices needed making during repair which involved many pipes having renewed languid edges. These required nicking to match the original type, and it was clear that the Leatherhead voicer used vertical nicks, not angled ones as at Great Packington. In both organs there are also nicks on the lower lip opposite those on the languid.
After testing the wind and the soundboard, the conveyances were made, and the front pipes could be installed and tested. Some of these have what appears to be the original tuning length on the back of the pipe top. A single slit for fine tuning is the same as at Great Packington, and with these made a pitch of a = 437.7Hz at 19°C was established. A meantone temperament of some sort would have been expected, and a system devised close to that which was tried at St Botolph’s, Aldgate. It is close to a fifth comma meantone, but with d# lowered so that the key of b major is not unusable. This follows Renatus Harris’s tuning instructions.
Martin Goetze, 19th September 2007
Goetze & Gwynn
 Case front with some stain
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 Bass end stop levers |
 Bellows folds |
 Martin cutting up a big pipe .. |
 .. and a small pipe |
 Martin trimming a pipe top |
 Dominic's Dentils |
 Valve cut-off roller |
 view into the oven |
