MONS, Belgium - Move over vuvuzela. A compact, Belgian-made trumpet dubbed the "diabolica" is gearing up to replace the South African horn as the noisemaker of choice at the next World Cup games in Brazil .
Its young designers said they are "overwhelmed by the flood of orders coming from all over the world", and predict that a million models will be sold by the time the month-long tournament starts on June 12.
Unlike the long, plastic vuvuzela - whose love-it-or-hate-it drone went global at the last World Cup in South Africa in 2010 - the "diabolica" is easier to carry, collapsing to 12 centimetres (five inches), and easier on the ear, its creators contend.
"The sound is nothing like the buzz of the South African vuvuzela, which made life a nightmare for television producers," said David dos Santos, 31.
But he and partner Fabio Lavalle, 26, won't reveal the "secret" they say makes the difference.
The trumpet is already a big hit in Belgium, where stadiums ban both vuvuzelas and, for safety reasons, canister fog horns, an extremely loud, pressurised device more at home as part of a safety kit on boats.
"We never expected such a success," said Dos Santos.
Nearly 300,000 "diabolicas" - named after Belgium's "Red Devils" football team - have been sold since the end of last year and to keep up with demand, some 15,000 make their way daily from a Madrid factory to the plant in the southwestern Belgium city of Mons where they are assembled and packed for shipment.
"It was actually a Spanish friend, a Real Madrid fan, who came up with the idea after a friend was blocked from the stadium with a canister fog horn," said Dos Santos.
"He thought about how birds make sounds, manipulating vibrations against membranes, and he tested thousands of membranes before finding the right one.
"This membrane is the secret," said Dos Santos, who owns the patent.