March 27, 2004
Mark III
Final layout for the organ pipe design. The air goes through the narrow channel, see the diagram. The airflow hits the movable edge and creates turbulance. This is where the sound is generated. The key to making the pipe work is the moveable edge.
By allowing the edge to move it is possible to line it up with the centre of the airflow. The movable edge is simply a fold of card which can slide up and down in the throat of the pipe. Once lined up the pipe makes a wonderful sound! Posted by robives at March 27, 2004 09:59 PM
I have been wrestling with the same problems for some time now! There are a few books that suggest heights and scales ( the rate at which the lenght and depth reduces with reducing the length). Altering the height of the mouth is also very important. Have you built the pipes with closed (stopped) ends or open? This will also affect the playing qualities- stopping will lower the pitch by an octave, as well as possibly making the pipe sound at a lower air pressure. I have also managed to build piccolo pipes, like those found on fairground organs using card and paper- they are loud, high and look really different. Would you be interested in them as an alternative?
If you try making the pipes out of thinner card- e.g. mounting board, they can also work very well, although varnishing them seems to improve them a lot.
cheers
Andy Young