Several beeps of an active sonar. This is a low frequency sonar (long range but low definition). It is a sine wave of 1190 Hz frequency easy to put in loop. In reality, a military submarine usually has passive sonar, more sonar info: en.wikipedia.org/wiki/Sonar. UCS Category: BOATSub. Duration: 00:21.
Cinema projector (35mm Kinoton, FP30) without fan or lamp: Getting Started, then roullage extinction (Sound: Before mechanism). Can synchronize its 0070. UCS Category: COMAv. Duration: 00:41.
Sound of a small electric drill on battery. It is equipped with a concrete bit, and drills concrete. Two drill strokes each followed by a removal of the bit, then the machine is turned off. UCS Category: TOOLPowr. Duration: 00:41.
Small brook, blackbird, fly, birds, 2 different sounds of the brook (on the left, a deeper "meander" and on the right another shallower one, so I put myself in the middle!). Forest of Signy-l'Abbaye (Ardennes). UCS Category: AMBForst. Duration: 03:49.
Omnipresent sun or overwhelming heat, this is a sound effect that is widely used in films. I made this sound in the studio, failing to find it in nature. Maybe it's an insect? If you know more about the source of this noise, tell me. According to another anonymous visitor: The Arizona Apache Cicada is the loudest. UCS Category: ANMLInsc. Duration: 00:44.
Starting a NAS computer server. This is a Synology with 4 HDD hard drives. Fan noise, start disks one by one, then work. UCS Category: CMPTDriv, UIData. Duration: 03:28.
