In the following clips Cormac ó hAodáin discusses aspects of horn construction.
Very Curly
The reason the horn is so wrapped up, is that it would be very difficult to transport approx. 17 foot of metal that was just in a straight line. You´d have to have an extremely large car with a very big estate built onto the back.
Enlarge the image opposite to compare the single horn and double horn.
Conical Bore
The horn has a conical bore, which means that it starts small at one end and gradually widens. You can see a big difference between the start of the mouthpipe and then where it flares out to the bell. It´s not conical throughout the whole instrument; it is cylindrical within the valve section, but the top of the mouthpipe to where the valves start is conical and then it´s cylindrical right throughout the valve system. When it comes out of the valve system, once again it becomes conical.
The Mouthpiece
The mouthpiece comes in different shapes and sizes: different diameters right at the small end and the bore of the mouthpiece and the size and depth of the lip of the mouthpiece can be wider or less wide. It does actually make an enormous difference, which is incredible in such a small piece of metal. With even a difference of a quarter of a millimetre professional players will hear the difference. Sometimes people use different mouthpieces for specialist things, for example in the extreme high or very low registers. Traditionally a smaller mouthpiece will be used for the higher register, and a bigger mouthpiece for the lower register so that you can get more air through.
Making a Sound
The way it works is that by buzzing my lips against the mouthpiece I cause the air inside the instrument to vibrate and the sound resonates from that.
clip 1 -
The valves...
clip 2 -
The name of the instrument
...
clip 3 -
The history of the horn...
clip 4 -
The tenor horn is no relation to the French horn.
clip 5 -
Hand and playing position...