In order to return the organ to first-class condition, and once again make it the finest organ in Cheltenham, a comprehensive programme of work needs to be carried out, including:
Reservoirs, Concussions and Wind Trunks
The large main reservoir (some 4.2m x 1.8m in floorplan!) and four smaller reservoirs need to be removed and re-leathered. This involves careful dismantling of the reservoirs, stripping off of the old, perished leather, and replacement with new leather which will last for another century.
Similarly, the concussion bellows (small bellows which absorb the small shocks in the supply of wind caused by sudden demand) need to be removed and releathered.
The wind trunks (the large wooden and metal ducts which convey wind from one part of the organ to another) need to be removed and repaired.
The corner of one of the organ's 6 reservoirs, showing patches of leather to cover holes where the original leather has perished.
Solo change-over machine, showing the pneumatic tubing which runs to the soundboard.
Key and Stop Actions
The actions (mechanisms which bring the correct pipes into play based on the movement of stops and keys at the console) date from between 1899 and 1994. The key action for the Great organ dates from 1994 and is in good condition, but the other actions are showing signs of their age.
The 1899 tubular pneumatic actions were partially converted to electro-pneumatic in 1952-3, with the use of change-over machines. The result is a very complex mechanism which is difficult to maintain and cumbersome. As the leatherwork within these mechanisms is perishing; they are no longer as prompt or reliable as they should be. The best way forward is to remove the over-complicated change-over mechanisms and replace these with new electric primary actions which are more reliable and react more promptly to the organist's actions at the console.
Similarly, the stop actions still use the cumbersome 1899 pneumatic machines; partially converted to electro-pneumatic, again with change-over machines, which are noisy and becoming unreliable. Modern electro-magnetic solenoid units will be much more reliable and operate almost silently.
Both of these changes will result in far less pneumatic tubing within the organ, improving access for tuning and maintenance and increasing the reliability of the organ for the future.
The soundboards (the large structures on which the pipes stand) and chests around the organ need to be removed and thoroughly restored. Decades of atmospheric change have taken their toll on the internal structure of the soundboards and they need to be completely disassembled and carefully re-built to give them another 130 years of life.
Choir organ pipework.
An example of new primary action magnets similar to those which will be fitted to the chests currently in the organ, replacing the worn-out pneumatic change-over machines.
To allow the addition of a new Principal/Fifteenth unit to the Pedal organ, and the relocation of the Tuba, new chests will be constructed.
Moving the Tuba to are more prominent position will improve its tonal projection into the nave and allow its commanding tone to be heard over the rest of the instrument. At the moment, it is easily dominated by the Great Organ, which makes it much less effective.
As the Tuba currently resides on the Solo soundboard, moving it to a new location will require the construction of a new chest.
Swell and Solo boxes
The Swell shutters open approximately 45 degrees to face east. This will be altered so that the shutters open to face west, which should improve the projection of tone into the nave.
The Solo shutters are presently disconnected (not having been reconnected when the shutter front was returned to its original position) and the mechanism needs to be reconnected.
Shutters on the front of the Swell box. These will be reversed to open west.
1953 Nicholson & Co console.
The four-manual console has been in constant use since 1953. After tens of thousands of hours of playing, it too is becoming rather worn out and needs a thorough refurbishment. The keyboards and pedalboard will be restored, thumb and toe pistons replaced (with an enhanced piston provision) and the drawstop solenoids replaced with new.
The various tonal changes since 1953 have also resulted in the presence of several engraving styles on the drawstops, with some stops bearing the incorrect name. Miss-matched stops will be re-engraved in the same style as the 1953 stops and incorrect stops will be re-engraved with the correct stop names.
The provision of couplers will also be revised to improve the flexibility of the organ.
The organs 2,500+ pipes need to be carefully removed, repaired where necessary, and thoroughly cleaned before receiving attention from specialist staff to ensure they are all speaking properly.
Great organ pipework. The stone wall of the transept is visible on the right.
A new Principal/Fifteenth unit will be added to the Pedal organ. This will provide more independence and definition to the pedal line, particularly useful in the performance of contrapuntal music, such as fugues, where the use of manual-to-pedal couplers can compromise the clarity of the individual lines within the music.
A new Harmonic Gemshorn stop will be made, in Hill style, for the Solo organ. Such a stop was present when the organ was built in 1887, but was lost in 1952-3 when tonal changes were made to the organ in keeping with the fashions of the time.