The Tuba The tuba, with a compass of over three octaves, is the lowest-pitched and most recent member of the brass family. The deep tones are ideal for supporting the lower sounding brass, the tubas play the same role as the double basses in the string section. The adopted orchestral instrument in the tuba family is the bass tuba in F. Others in the family include the E flat bass tuba, the euphonium, the double-bass tuba in B flat. Next instrument - the Timpani Previous instrument - the Trombone Back to the Orchestra construction of the tuba Shape and components: The tuba is built in various sizes, and the size of the larger tubas often rivals that of the player. The orchestral tuba has 4 metres of wide, conical tubing expanding into a large bell; these factors also contribute to the instrument's deep tone Sound production: As the lower notes require more tubing, this air takes longer to travel out the bell, therefore the sound is delayed longer than the higher notes. The tone is muffled due to the fact that the bell is facing upwards instead of towards the audience. Like the trumpet, valves are used to vary tube length and up to four valves are used on a tuba. A deep, cup-shaped mouthpiece is used and conical mutes can also be inserted into the bell