Keyed bugle

What it means

The keyed bugle (German Klappenhorn) is a brass instrument whose tonal range is extended not by valves but by keys mounted on the side. As with woodwind instruments, these keys open holes in the tube wall and thereby shorten the effective air column, so that notes lying between the natural notes become reachable. It was built above all in the early nineteenth century, in soprano register as the keyed bugle and in a low register as the ophicleide. After the establishment of valve technique, this type of construction largely disappeared; the transition dragged on over decades.

Musical use

In the time before the general introduction of valves, the keyed bugle was one of the few brass instruments with a complete chromatic scale and was accordingly used in military music, town music, and the orchestra. Individual works of the time are expressly written for it. Tonally it is less uniform than a valve instrument: notes that arise via open keys sound more open and brighter than the closed natural notes. This unevenness counted as a disadvantage and led to its being superseded, but is today understood in historical performance practice as a characteristic colour and deliberately made audible.

Performance practice

Whoever plays such an instrument works with two systems at once: the embouchure for the natural notes and the keys for the intermediate notes. First practise the harmonic series securely before you add the keys. Expect uneven response and volume between the two note groups and balance them with air guidance instead of forcing the differences. Check the pads, because leaking keys make the notes concerned unusable. In an ensemble with other historical instruments, the pitch is to be settled beforehand. Reproductions differ considerably in bore and key arrangement.

Bear in mind that the intonation of individual key notes differs from instrument to instrument: make a fingering chart of your own for your specimen and record which notes must be corrected. Play rather restrainedly, because the tone quickly becomes unclean under pressure. For the audience a brief note in the programme is worthwhile, because the unequal tone colours are otherwise heard as a flaw and not as a characteristic.