A soloist starts playing his string bass on a town plaza.
Much like many of the musicians who dot downtown pedestrian malls in American cities, there is a hat on the paving stones in front of him for donations.
But then comes a cello. And a bassoon.
The melody becomes apparent, "Ode to Joy" from Beethoven's Ninth Symphony.
Violins join in and the crowd's cellphone cameras appear en massse. Boys climb lampposts to get a better view. A crowd of brass and woodwinds appears, and percussion is likewise rolled out onto the plaza.
This flash mob reveals itself to be the Valles Symphony Orchestra and the Lieder, Amics de l'Opera and Coral Belles Arts choirs.
They were put up to the performance by Banco Sabadell on the occasion of its 130th anniversary. Company officials said they wanted to find a way to pay homage to their city as part of their publicity campaign "Som Sabadell" (We are Sabadell).
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