It's called a SOUND UPCUT.  You write the scene then, for example...
 
SOUND UPCUT:  A Chainsaw BUZZ.
 
                                                          CUT TO:
 
EXT.WOODSITE.DAY
 
A MAN weilds a supercharged chainsaw at a pair of unlucky tourists
 
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Online resources for film/TV studies may be found at ScreenSite
http://www.tcf.ua.edu/screensite