These are the pipes, usually visible as the front row (or rows) on most organs. The picture shows my organ with the front finally in place complete with HomeBase mouldings.
There are thirteen (of the 14) of these and once again, “poor old” B natural is missing.
This lack of B nat. means it is not possible to play in the major keys of C, G, D etc. but all is not lost, we simply have to transpose the music to one of the five keys we can arrange in.
Some smaller organs make do with this single row of 13 melody notes (pipes).
The organ I have built has another three rows or “ranks“ of these 13 pipes, one behind the other. These extra ranks of pipes are not all the same; they sound the same (or similar) note, but of a different quality or tone. Therefore one hole on the tracker bar can now actually sound up to four pipes simultaneously depending on which rows are selected.
On a church organ these are known as the “stops”, hence the term to “pull out all the stops”. They have such names as Diapason, Bourdon and Open Flute.
My first two rows are Stopped Bourdon, the third row are Piccolo and the fourth row are Open Flutes.
Why two ranks of Bourdon?
Are they not the same?
They are constructed the same and to the same dimensions but they are tuned very slightly different. We start off by tuning the two notes the same (ie C to a C) and then by tapping the stopper on one of the pipes down “a whisker”, the sound of the two will move from unison to a slight “beating”. This effect is known as Celeste (from the French…‘heavenly‘).
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