Noise of a helicopter. Recording from outside. Wind noise in the paddles. Acute and powerful sound. Sound is difficult loopable. UCS Category: AEROHeli. Duration: 00:05.
Telephone tone when the line is busy, in France. This is a sound wave frequency of 440 Hz sinusoidal, slightly clipped. Half a second, every second. This sound is easy to loop. UCS Category: COMTelph. Duration: 00:10.