Constructing a 42 key hybrid organ.
Further i wanted complete against my principles this organ provided with control electronics. Imagine the labour intensive work of making organ rolls and the great supply of music for this organ, it seemed to me the best solution. Nevertheless i did not want to say goodbye to the nostalgic organ roll and so i got the idea to make a hybrid organ: playing on MIDI files and paperrolls. The trick? very simple. On every connection towards the tracker bar i mounted on the valve chest a small block of hardwood, where whe commandwind could escape though a second channel and a electromagnet and so both playing options are possible.
With my already aquired knowledge, existing construction plans, tips of good friends i started with the project. First i made on the computer several drawings and soon i got a concept for the housing and the groundplate, in which all the conducts (air channels) should have been made.
One problem should to be solved. How to decorate it and which name you give your "creation". An organ according German construction principles and still a Dutch look. I am absolutely not an artist in decorating so the method should be simple. Caused by a wall tile i got the idea to paint the organ complete white and forseen it with dark blue decorations as if it was a "Delft-blue" organ. The name? The best name you can use is the name of your wife.....(Marietje means Little Mary) All decorations were first drawn with carbon paper on the organ and afterwards repainted with a small pencil.
Through a collegue hobbyist i could get on thickness made mahony wood. Though this the making of the first two registers on melody pipes was soon done. With in total 3 registers "Marietje" has 3 x 22 melodypipes, 12 accompainiment pipes and 8 bass pipes finally 86 organ pipes.
The six lowest bass pipes are traditionally mounted on the bottom side. By studying the german factory organs very well, i saw that the beards were slanted. This results in a remarkable improvement of the sound.
The other two basses and the lowest accompaniment pipes are hidden behind the cut out lilies near the bellows. De overige twee bassen en de laagste accompagnementspijpen werden achter de uitgezaagde lelies verstopt bij de balgen. The other accompaniment pipes are positioned in the corners of the melody pipe room.
The bellows has been made according the 20 key organ, only the dimesions grew proportionally. This results in a grater pumping movement so that more air was available. In stead of using great pieces of leather i have employed ropes of leather and for the folds airplane plywood.
Also i have employed an other shape in the corners, though which a greater rendement has been achieved.
Gradually the separate parts were completed and the organ could be set together. On the below standing photo you can see clearly the position of the bellow with above the valve chest. You can see also the by-pass blocks with electromagnets and the spaghetti of hoses for the tracker bar.
The electronics exists in fact of two components. A MIDI player and a driver card, which provides the electormagnets of a signal. In the MIDI player a SD card up to 2 GB is possible. Assuming a size of 25 KB for each song, it is possible to store 80.000 songs in this organ, with other words 80.000 organ books or rolls. Finally the power has been supplied with a 12V 7A battery, which provides an uninterrupting playing time of 14 hours!
Remaining a car below it and see "Little Mary" in it's full glory. At this moment "Little Mary" has made already several performances. Now the making of traditional rolls for this organ has to be done......