Known in the US as an alto horn, in German as an althorn,
and in the UK as tenor horn, this instrument is an aerophone
(i.e., a brass wind instrument sounded by buzzing the lips) in Eb, with a conical
bore (gradually widening), normally using a bell-shaped mouthpiece. It is most
commonly used in marching bands and brass groups, where French
horn takes the corresponding parts in symphonic groupings. It has a mellow
sound, blends well, and serves as the voice between trombone
(or baritone horn,
in Bb below) and
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trumpet or cornet
(in Bb above). Its lowest note is concert A below C below middle C, and its
highest is Eb above C above middle C. It was invented in the mid-1800s
by Adolphe Sax,
a Frenchman who is best
remembered for inventing the saxophone,
as a middle voice in the group known as "saxhorns." It has been made in various
forms: most common is a sort of mini-tuba
shape, with the bell pointing upward, which helps the voice blend before reaching
the audience; the solo horn often looks like an enlarged trumpet, with the bell
pointing forward, projecting more toward the audience; another variant has the
bell facing backward (for military marching bands that preceded the soldiers,
thus helping them hear better and keep better time in marching).
