The flute is the instrument that serves as the soprano voice in most bands, orchestras, and woodwind groups. Most flutes are made of metal and consist chiefly of a tube with a mouthpiece near one end. The musician holds the flute horizontally and blows across an oval shaped hole in the mouthpiece. At the same time, the musician presses levers on the flute, called keys. The keys, when depressed and released, open and close tone holes on the flute to produce different notes. The concert flute, which is tuned in the key of C, is the most popular flute and has a three octave range. Other members of the flute family include the piccolo, the alto flute, and the bass flute.