The tuba is the largest, lowest sounding, and youngest instrument in the brass section. It produces a full, rich and powerful tone that provides a rhythmic and harmonic pulse for the orchestra, and not much melody. The tuba is used in marches and other compositions where it is important to have a strong beat and bass line.
The tuba rests on the player’s lap. Stretched out straight, the tube of a tuba could be as long as 35 feet. The player uses a mouthpiece and has four or even five valves to help change the pitches. Tubas can be made in many different shapes and ranges.
The tuba is used in the orchestra to provide foundation for the harmony.