The vuvuzela is a horn, with an inexpensive injection-moulded plastic shell about 65 centimetres (2 ft) long, which produces a loud monotone note, typically around B♭ 3. Some models are made in two parts to facilitate storage, and this design also allows pitch variation. Many types of vuvuzela, made by several manufacturers, may produce various intensity and frequency outputs. The intensity of these outputs depends on the blowing technique and pressure exerted. The indoor noise level caused the U.S. NCAA to permanently ban them after the 7 February 1987 Division I Men's Ice Hockey game between the Brown Bears and the Rensselaer Polytechnic Institute Engineers. The noise was so extreme that Brown formally complained and "The RPI Rule" was universally adopted.
A 2010 FIFA World Cup crowd blowing vuvuzelas
Some vuvuzelas carry a safety warning graphic.
Wesley Sneijder blowing on a vuvuzela
A brass instrument is a musical instrument that produces sound by sympathetic vibration of air in a tubular resonator in sympathy with the vibration of the player's lips. Brass instruments are also called labrosones or labrophones, from Latin and Greek elements meaning 'lip' and 'sound'.
Six high brass instruments Left, from top: A reproduction baroque trumpet in D, a modern trumpet in B♭, a modern trumpet in D, a piccolo trumpet in B♭ (octave higher), and a flugelhorn in B♭. Right: a cornet in B♭.
A tenor horn (alto horn) in E♭, baritone horn in B♭, and euphonium in B♭
Brass instrument piston valves
Flugelhorn with three pistons and a trigger