Sheet metal french horn - has switching valves for three tube lengths, combined in tandem valve placed behind main valves

摘要

The bugle has three different tube lengths determining the keynotes of the oscillating air column. Its parts are arranged in three parallel planes above each other. At a certain instant the tube length of one plane is opened for the air flow by a cylindrical switching valve operated by a lever. The tubes can be lengthened or shortened by lever operated main cylindrical valves in order to produce a chromatic effect. They are similar to each other and are arranged in a row. Switching valves are partly combined in a tandem valve (14) with two independent driving shafts (18, 19) placed behind the row of main valves (3032).