Two helicopters landing and taking off one after the other. Sound recording during the open day of the UIISCI in Nogent-le-Rotrou in France. UCS Category: AEROHeli. Duration: 03:21.
I sing in overtone. Overtone singing is a vocal technique for producing a vocal timbre characterized by two notes of different frequencies. My first voice is a root A, my second is a whistle. more information on this song: en.wikipedia.org/wiki/Overtone_singing. UCS Category: VOXSing. Duration: 00:13.
The sound of a detector. Like a metal detector. Generated with a computer. This is a sawtooth wave, with a frequency of 465 Hz. UCS Category: BEEPAppl. Duration: 00:03.