Tubas a litte bit of history..
The tuba is the largest and lowest-pitched brass instrument. Sound is produced by vibrating or "buzzing" the lips into a large cupped mouthpiece. It first appeared in the mid 19th-century, making it one of the newest instruments in the modern orchestra and concert band. The tuba largely replaced the ophicleide. Tuba is Latin for trumpet or horn.The horn referred to would most likely resemble what is known as a baroque trumpet.
Types and construction..
Tubas are found in various pitches, most commonly in F, E♭, C, or B♭. The main tube of a B♭ tuba is approximately 18 feet long, while that of a C tuba is 16 feet, of an E♭ tuba 13 feet, and of an F tuba 12 feet. The instrument has a conical bore, meaning the bore diameter increases as a function of the tubing length from the mouthpiece to the bell. The conical bore causes the instrument to produce a preponderance of even-order harmonics.
A tuba with its tubing wrapped for placing the instrument on the player's lap is usually called a concert tuba or simply a tuba. Tubas with the bell pointing forward (pavillon tournant) instead of upward are often called recording tubas because of their popularity in the early days of recorded music, as their sound could more easily be directed at the recording instrument. When wrapped to surround the body for marching, it is traditionally known as a hélicon. The modern sousaphone, named after American bandmaster John Philip Sousa, resembles a hélicon with the bell pointed up and then curved to point forward. Some ancestors of the tuba, such as the military bombardon, had unusual valve and bore arrangements compared to modern tubas.
Materials and finish..
The tuba is generally constructed of brass, which is either unfinished, lacquered or electro-plated with nickel, gold or silver. Unfinished brass will eventually tarnish and thus must be periodically polished to maintain its appearance.