The tuba is the largest instrument in the brass family. Like the cornet, it has a conical bore and consists of a gradually widening tube of brass folded round on itself to save space. The sound, which comes out of the flared bell, is made by blowing a "raspberry" with your lips into the cup-shaped mouthpiece. Basically what happens is that your lips vibrate, a bit like the reed of a clarinet, and when this vibration passes through the specially shaped bore of the tuba it becomes musical sound. Different "open" notes are made by varying the tension of your lips (your teacher will explain how to do this), and you can produce the notes in between by using different combinations of valves.
Tubas usually have three valves, and these divert the air through little extra lengths of tubing, which makes the instrument temporarily a bit longer and therefore deeper.
The tuba's ancestry includes primitive instruments like the Roman tuba, which some claim is the source of the name for the instruments. Around the beginning of the seventeenth century, the serpent was developed. This instrument was in the form of a letter S and was approximately eight feet long. The serpent is generally accepted as the predecessor of the modern bass tuba.
Tubas have an important job to play to orchestras, wind bands and brass bands. They are even sometimes used in traditional jazz bands. All this means that if you take up the tuba you find there are some excellent opportunities for group music-making and, because tuba players aren’t that common, you’ll probably find that you are very much in demand!
They are quite big and bulky to handle, so most people don’t start to play the tuba until they are about 12 years old or when they are big enough to hold the instrument. Hold it in front of you on your lap with the mouthpiece to your lips and the bell pointing upwards. You operate the valves with your right hand and support the instrument with your left hand.
As long as you’re big enough to hold it, the tuba is fairly easy to start, as you don’t need as much puff to get a sound out of it as you might expect. It's actually the long thin instruments that have a narrow bore (like trumpet and horns) that need the most effort. However, it is possible to start on a similar instrument, such as the smaller euphonium, baritone or tenor horns and then transfer to the tuba later on.
If you do decide to go straight to the tuba, you’ll need to work out what size to start off on. Check with your teacher, although they are likely to suggest a "small E flat" or "small-bore E flat" instrument which will be a manageable size. (You can always switch to a large-bore instrument later on.) When you play C on an E flat tuba, it actually sounds like an E flat on any normal instrument (which means the tuba music you buy will have been specially transposed to suit).
Be aware that because of the size and weight of tubas, they are not the easiest instruments to transport. They don't usually come apart, and are carried in rigid cases. Some players have cases with wheels on the bottom to make them easier to manage.