The organ at St Matthew's has 1266 pipes and these enable it to give the rich and varied sound associated with organ music.
Some of these are on view and provide the impressive decoration above the keyboard console. Pipes which produce the lowest notes, and need to be very large, stand away from the console in the corner of the gallery.
The large pipes are controlled from the foot pedals, together with others which stand behind the organ under the rose window.
Most of the pipes, however, are arranged immediately behind the keyboards in two grids. The columns of each grid are controlled by the keys, and the rows of each grid are controlled by the 'stops'. Each grid has its own keyboard. Some of these pipes can be seen in this view, which shows the right hand side of the organ.
All the pipes have to be supplied with air at a constant pressure, which is provided by a pump feeding a large reservoir in the form of bellows.
When the pump is switched on, air fills the bellows and lifts the weighted top. A simple mechanism controls the incoming air supply, so that the volume of air in the reservoir remains reasonably constant. The weight of the top determines the pressure of the air. This air is distributed to a number of windchests on which the various groups of pipes are mounted.
Pipes are made to sound by opening valves (or pallets), thus connecting them to the air under pressure - just like playing a penny whistle. Some pipes have brass reeds which vibrate as the air passes over them; these can sound more like clarinets and brass instruments.
Pipes generally produce a fixed intensity of sound. To make some variation possible the pipes belonging to one of the keyboards are surrounded by a wooden enclosure. The front of this has 'venetian blind' type louvres to hold back or release the sound. These louvres are operated by a 'swell' foot pedal.
There are 24 controls called 'stops' at the sides of the keyboards, and these can be drawn out to preset which row of pipes will actually sound when a key is pressed.
Each of the two keyboards spans the same 4½ octaves. These days the control between the keyboard and the pallets is by electrical circuits operating electro-magnetic solenoids.
This view also shows two of the three foot pedals which control preset common combinations of stops. Without these the organist would find it very difficult to play the organ.
The organ in St Matthew's Church was originally built for a Wesleyan Methodist Church in the High Street, Pontypool. It was installed there in 1884 at a cost of £435. The church closed in 1958 and the organ was transferred to St Matthew's in 1960. The cost of removal, renovation and installation was £2918.
The builder of the instrument is unknown, but Vowles of Bristol is a strong possibility. The instrument is not in its original condition, having had a number of alterations made to it, but it still retains about half of its original Victorian pipework. Originally the organ was completely mechanical, with a person behind operating the pump. Later the air would be supplied by an electrical pump. With the transfer to St Matthew's, the organ was converted so that electricity played a larger part in the operation.
This photo and the caption below are from the Wimbledon Borough News, July 1960. It was kindly supplied by Mr Peter Ayers for the church's archive.
"Mr A H Ayley, organist of St Matthew’s Church, West Wimbledon, standing by the church’s new organ in the now completely restored building, as Mr Peter Ayers, deputy organist, plays. The church restoration fund is being closed at a dedication ceremony on 16th July."