Euphonium repertoire euphonium was embraced from its earliest days by composers and arrangers in band settings, orchestral composers have generally not taken advantage of its capabilities. Nevertheless, there are several orchestral works, a few of which are in the standard repertoire, in which composers have called for a tenor tuba, a German "Tenorhorn"¹, a Wagner tuba, or a French tuba in C. In all of these cases, the composer's desired effect was that of "tenor-voiced, valved brass" instrument – and in many of these cases the euphonium is substituted for the called-for instrument, either because the instrument is obsolete (French C tuba),
Tuba of notes. Prior to the invention of valves, brass instruments were limited to notes in the harmonic series, and were thus generally played very high with respect to their fundamental pitch. Harmonics starting three octaves above the fundamental pitch are about a whole step apart, making a useful variety of notes possible. The ophicleide used a bowl-shaped brass instrument mouthpiece but employed keys and tone holes similar to those of a modern saxophone. Another forerunner to the tuba was the serpent, a bass instrument that was shaped in a wavy form to make the tone holes accessible to the player.