When I went to Denmark in 2002, I made a point of visiting Frobenius Organ Builders in Kongens Lyngby where I had learned my trade before emigrating to Canada. My intent was to ask for a set of organ plans so that I in my spare time could build a small organ in my basement. Imagine my surprise when the answer was “sure, but wouldn’t you rather have a whole organ?”
The organ in question had been built by Frobenius in 1968 and installed in Resen Church near Skive. When Resen Church acquired a larger instrument, their old organ became obsolete. Though the organ was in good shape no buyers could be found so it was put in storage. That Resen Church would be willing to donate the organ to the Danish Church in Vancouver was definitely a possibility.
When I returned to Vancouver, I presented the offer to the Danish church. The general consensus soon emerged that we could not pass up this opportunity to own a genuine instrument even if there was nothing wrong with our electronic organ, which was more versatile than any pipe organ we had room for. Resen Church was contacted and they confirmed that they would indeed donate their organ, Möbler Furniture in Richmond donated the transportation, and an organ fund was established to cover all other costs.
The organ arrived in the summer of 2003, and was hoisted to the choir loft where I began to work on it. I painted the organ box in the grey and burgundy colours of the interior of our church; I serviced and cleaned every part of the organ; I had the blower rewired for 110 volts and moved it outside the organ box to make room for the set of pedals we purchased from Frobenius. For the first year or so, the pedals were simply coupled to the manual, but during 2006 I built a set of wooden pipes to be played by the pedals.
In January of 2004, our traditional Pea Soup & Pork Dinner was extended to a Pipe Polishing Party. We had great fun making the 280 pipes shine. On Sunday February 8th, the organ first played for a service, and on Sunday February 29th, we had our first organ concert.
I am grateful for this opportunity to practise my old trade, and I look forward to caring for our organ for many years to come.
How our organ works / The physics of an organ pipe
The air enters through the bottom of the pipe and hits the sharp edge at the front of the pipe making the air vibrate. An animation showing destructive interference in an open organ pipe.Those vibrations that do not fit exactly in the pipe drown themselves out as they interfere with themselves. In the animation on the left, the blue curve is the wave that bounces up and down in the pipe, and the red curve is the net result: the sum of the blue curves. Notice how the red curve becomes straight after a few bounces, indicating that the wave has annihilated itself—and then the animation starts over.
Those vibrations that do fit exactly are amplified by resonance producing the primary tone and overtones of the pipe. In the animation on the left, the blue curve bounces up and down on top of itself so that the amplitude of the red curve, the sum of the blue curves, gets larger and larger—until the animation restarts.
The length of the pipe determines which waves fit exactly inside and thus the pitch of the tone the pipe makes. Several wavelengths fit—the pictures to the right show the first few. The blue curve is the primary tone, the remaining curves are overtones. The shape and design of the pipe and the composition of the metal alloy the pipe is made from determine the relative strength of the overtones and thus the “colour” of the sound
The mechanics of our tracker organ
Our organ has five stops (or voices):
Principal 4’
This cylindrical pipe is open at the top where a cuff allows the organ tuner to slightly change the length of the pipe and thus its pitch.
Spidsfløjte 2’, Spire Flute
The Spire Flute tapers gradually to a narrow opening at the top.
Oktav 1’, Octave
The Octave is a Principal pipe at quarter length and thus sounds two octaves higher.
Gedakt 8’, Gedeckt
The Gedeckt pipe is cylindrical like the Principal but covered by a cap at the top. The length of the of the Gedeckt 8’ pipe is the same as the Principal 4’ pipe but a covered pipe sounds an octave lower—hence the eight-foot designation.
Rørfløjte 4’, Rohrflöte
The Rohrflöte is also covered by a cap, but the cap is perforated by a narrow tube that descends into the pipe as in the picture on the right.
Gedakt 16’, Gedeckt
This set of wooden pipes is controlled by the pedals.
Our organ is a small tracker organ: a mechanical organ. An electric blower and weighted bellows provide constant air pressure. When the organist presses a key, a set of levers and cranks open a valve letting air into a narrow chamber under the five pipes that belong to that key, one pipe for each voice of the organ. The organist chooses which of the five pipes shall sound by pulling or pushing a knob that slides a thin piece of wood with holes in it under the pipes. If the holes line up with the pipes, air enters the pipe and it sounds, otherwise the pipe remains silent. This type of mechanism has been common in organs since the 15th century.
The drawing of the slider mechanism was kindly provided by Ted Rashleigh
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