Caxirola

J Acoust Soc Am. 2013 Nov;134(5):4187. doi: 10.1121/1.4831358.

A first look into the caxirola-Official music instrument of the Soccer World Cup 2014.

Pozzer T, Paul S.

Source

UFSM, Undergraduate Program in Acoust. Eng., DECC-CT-UFSM, Av. Roraima 1000, Camobi, Santa Maria, RS 97105-900, Braziltalita.pozzer@eac.ufsm.br.

Abstract

For the 2014 Soccer World Cup Brazilian Musician Carlinhos Brown created the caxirola as the official music instrument, adapting an old African instrument-the caxixi. Both caxixi and caxirola generate sound by hard particles impacting on the walls of a closed basket. While the basket of the caxixi is made of natural materials the basket of the caxirola is made of environmentally friendly polymer. Remembering the acoustical impact of the vuvuzela in 2010 as quite negative it was decided to study the acoustics of the caxirola. First, the way people will use the caxirola in terms of arm's excursion and velocity of shaking was studied. It was found that the caxirola was used moving it longitudinally and perpendicularly to its main axis, both in vertical direction. Spectra of the sound emitted by the caxirola and caxixi moving perpendicularly are quite similar with slightly more low frequency energy. However, when subjected to longitudinal movements, spectra are different. For the caxirola, the particle impact sound on the walls is the same for all impacted walls but for the caxixi, where lateral walls are of different material than the bottom, the spectra shows more energy for impacts at bottom.