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1.
Phrase. drop (verb) tones (noun)

The act of transmitting an electronic tone or set of tones by radio signal to alert a person or group of people. Terminology typically used by public safety dispatchers and emergency personnel.
Engine 11 to Fire Dispatch, drop tones for an additional EMT to respond to the scene of the accident.
Bill Vによって 2005年07月29日(金)
 
2.
The sound an object makes as it's falling onto a surface.
I could tell by the drop tone that it was your pen that fell out of your pocket, not your ring.
pentozaliによって 2012年08月21日(火)