All sounds CC-by-sa Julien Jorge, produced with the following samples.

burst-1:
CC-0 gniffelbaf http://www.freesound.org/people/Gniffelbaf/sounds/82117/

burst-2:
CC-0 gniffelbaf http://www.freesound.org/people/Gniffelbaf/sounds/82121/

burst-3:
CC-0 Mart1001 http://www.freesound.org/people/Mart1001/sounds/54012/

burst-4:
CC-0 lematt http://www.freesound.org/people/lematt/sounds/54874/

