A Dictionary of Music and Musicians/Euphonium
EUPHONIUM. A name given to the bass instrument of the Saxhorn family, usually tuned in B♭ or C. It only differs from the barytone Saxhorn in the larger diameter of its bore, which thus produces a louder and somewhat deeper quality of tone. It is usually furnished with four valves, sometimes even with five, the first three worked by the fingers of the right hand, and severally depressing the pitch by a semitone, a tone, and a minor third; the fourth by the left hand applied to a different part of the instrument, and lowering the pitch by two tones and a semitone.
From the gradual disuse of the Serpent and Ophicleide, the Euphonium is becoming the chief representative of the eight-foot octave among the brass instruments; with the exception of the few notes attainable on the French horn in that register. In quality it is however less sympathetic than its forerunners, and less able to blend with the stringed instruments. It therefore serves chiefly as a solo instrument, in which capacity it affords considerable support to the brass or military band. It possesses the usual harmonic series of open notes. Its compass is to a considerable degree dependent on the lip of the individual player. The fundamental note is obviously C or B♭ according to the pitch of the instrument, and the gap between this and the next harmonic above is more or less bridged over according to the number of the valves. The valves also admit of being used, together or separately, as integral parts of the tube, thus lowering the fundamental tone obtained, even to the extent of an octave.
[ W. H. S. ]