Euphonium Euphonium The euphonium is a large, conical-bore, baritone-voiced brass instrument that derives its name from the Ancient Greek word "euphōnos", meaning "well-sounding" or "sweet-voiced" ( "eu" means "well" or "good" and "phōnē" means "sound", hence "of good sound"). The euphonium is a valved instrument. Nearly all current models have piston valves, though models with rotary valves do exist. The euphonium may be played in bass clef as a non-transposing instrument or in treble clef as a transposing instrument. In British brass bands, it is typically treated as a treble-clef instrument, while in American band music, parts may be written in
British brass band horns, which are found in orchestras and concert bands. The standard instrumentation is as follows: The above totals 27–29 players, although in practice a band often has fewer than this. Spare seats may be filled for concerts and contests by players brought in from other bands, commonly known as "deputising players" or "deps". With the exception of percussion, bass trombone and some tenor trombone music, all parts are transposing and written in the treble clef with the instrument's lowest open note (B♭ or E♭) notated as middle C. This means that for every valved instrument, from the basses to the