Alarm Sounds

Air horn alarm sirens can create enormous sound pressure and spread it across big distances thanks to the horns mounted on the top of the siren. The construction of pneumatic alarm sirens is different from mechanical sirens. While the mechanical siren creates the airstream with the help of centrifugal forces, the pneumatic alarm siren uses a compressed air canister to pump the airstream into the siren head.

Air Horn Sound

The air-powered alarm siren (air horn siren) is easily identified by the horns mounted to the siren's head. Similar to a mechanical siren, the air horn alarm sirens create their signal by interrupting the air-stream cycle with the help of a perforated disc. The spinning disc inside the air horn siren's head is called a rotor; it is electrically powered. The air horn stream is directed through the holes in the rotor and external vents. The spinning motion of the rotor either opens or closes the holes, which creates the air horn sound of the siren that is then directed to several air horns. The air-stream that is needed for the operation of the air horn is created by an compressed air canister underneath the air horn siren.

Benefits of Air Horn Sirens compared to Mechanical Sirens

The main benefit of the air horn siren is the extremely high sound level it creates. Air horn sirens can reach a sound pressure level of 130db (!) at a distance of 20 meters. The other benefit of the air horn is the use of pressurised air. With the help of compressed air from a tank, the air horn sirens can create a very high sound level almost immediately, which is very important for the proper operation of a siren. Air horn sirens also need less electrical power than mechanical sirens (but they do require more maintenance).

Many of these high-performance air horn sirens were de-installed after the Cold War because they were no longer used. You can still see the pylons that those big old sirens used to be attached to (although nowadays they are more likely to house a mobile antenna than a siren).

Two-tone Air Horn Siren

Unlike mechanical sirens, air horn alarm sirens can create a two-tone sound. Pneumatic sirens with air horns are typically used on ships. The bigger the ship, the lower the sound of the air horn. The Sounddogs Archive features some very nice recordings of ship air horn sounds and pneumatic sirens.

Recording Air Horn Sound

Air horn sound can be recorded close to the air horn or in some distance to get some of the natural reverb - if you want that. Air horn sound like a big honk and can produce a very loud horn blast with high sound pressure levels. To avoid distortion when recording air horn sound, use a dynamic microphone like the legendary Electro Voice RE20 or the good old Sennheiser MD421.

Air horn sound are used as signal horns on vehicles like trucks, trains, busses or ships. Recording those air horns is pretty a lot of work. To get air horn sound effects from ships, find a good spot in harbours or large rivers where ship has to pass. Also ships uses their air horn sound to alert all other ships around, if they depart. The bigger the ship, the bigger the air horn sound, or the lower the air horn sound. So a supertanker has a very low air horn sound, while a sailing ship has a small air horn. This also makes sense, it would not be that comfortable to mount a huge air horn on your tiny boat.

Where to find Air Horn Sound

Field Recordist Rob Nokes recorded a great selection of air horn sound. He used hand held air horns and also recorded air horn sound from trucks and busses. The BBC Sound Effects Libraries contains also a nice selection of rare to find air horn sounds. The BBC engineers made some unique recordings from fog horns used on lighthouses. Their air horn sound different than the honking air horns. On lighthouses or even on sea traffic, Nautophone Horns are used. Nautophones works different than air horns. While air horn sound are created with compressed air, Nautophones creates their sound similar like alarm sirens or Klaxon siren. Nautophones uses a membran, activated or vibrated electrically while air horn sound are produced by slits or holes or with a rotating disc.

Library Waveform Filename add Price Description Channels Duration ShortID Category Subcategory Location Resolution Track ID Library
1 BBC Historical Sound Effects Library BBC Alarm Sound Effects, WarningSir_BBC-Historical_3 Sound Effects Waveform WarningSir_BBC-Historical_3.wav 3.50* Alarm, Siren: Warning Siren Sounded At Space Rocket Site. 2.0 0:18

Alarm

Alarm Siren

16 Bit / 44100 Hz 26419 BBC Historical Sound Effects Library
2 SoundStorm Library Sounddogs Alarm Sound Effects, Alarms-ElectronicCarAlarm_4 Sound Effects Waveform Alarms-ElectronicCarAlarm_4.wav 2.10* Alarm - Electronic Car Alarm - Ext - Medium Distant - Dual Tones W Fast Siren @ Tail 2.0 0:07 Alarm Alarm Siren 16 Bit / 48000 Hz 121972 SoundStorm Library
3 SoundStorm Library Sounddogs Alarm Sound Effects, Alarms-ElectronicCarAlarm_2 Sound Effects Waveform Alarms-ElectronicCarAlarm_2.wav 1.90* Alarm - Electronic Car Alarm - Ext - Medium Distant - Wailing Siren W Ascending Tones 2.0 0:05 Alarm Alarm Siren 16 Bit / 48000 Hz 121970 SoundStorm Library
4 Sounddogs Sound Library Sounddogs Alarm Sound Effects, Alarm,Car,Siren,Distant,Closer Sound Effects Waveform Alarm,Car,Siren,Distant,Closer.wav 3.50* Alarm: Alarm Car Siren Distant Closer 1.0 0:17 Alarm Alarm Siren 16 Bit / 48000 Hz 81419 Sounddogs Sound Library
5 SoundStorm Library Sounddogs Alarm Sound Effects, Alarms-ElectronicCarAlarm-M Sound Effects Waveform Alarms-ElectronicCarAlarm-M.wav 3.20* Alarm - Electronic Car Alarm - Medium Close Up - Very Obnoxious Siren Type 2.0 0:30 Alarm Alarm Siren 16 Bit / 48000 Hz 121976 SoundStorm Library
6 SoundStorm Library Sounddogs Alarm Sound Effects, Alarms-CarAlarm-Ext-Mediu_3 Sound Effects Waveform Alarms-CarAlarm-Ext-Mediu_3.wav 2.90* Alarm - Car Alarm - Ext - Medium Distant Cyclical Siren And Horn Signals W Engage And Disengage Chirps 2.0 0:22 Alarm Alarm Siren 16 Bit / 48000 Hz 121935 SoundStorm Library
7 SoundStorm Library Sounddogs Alarm Sound Effects, Alarms-ElectronicCarAlarm_1 Sound Effects Waveform Alarms-ElectronicCarAlarm_1.wav 1.80* Alarm - Electronic Car Alarm - Ext - Medium Distant - Wailing Siren W Descending Tones 2.0 0:04 Alarm Alarm Siren 16 Bit / 48000 Hz 121969 SoundStorm Library
8 Sounddogs Sound Library Sounddogs Alarm Sound Effects, Siren,Horns,Rise,High,Abrupt Sound Effects Waveform Siren,Horns,Rise,High,Abrupt.wav 2.60* Alarm: Siren Horns Rise High Abrupt 1.0 0:08 Alarm Alarm Siren 16 Bit / 48000 Hz 95086 Sounddogs Sound Library
9 Sounddogs Sound Library Sounddogs Alarm Sound Effects, Siren,Ambulance,High,Low,Modern Sound Effects Waveform Siren,Ambulance,High,Low,Modern.wav 3.50* Alarm: Siren Ambulance High Low Modern 1.0 0:56 Alarm Alarm Siren 16 Bit / 48000 Hz 95079 Sounddogs Sound Library
10 Sounddogs Sound Library Sounddogs Alarm Sound Effects, Siren,Toy,High,Low,Tiny Speak Sound Effects Waveform Siren,Toy,High,Low,Tiny Speak.wav 2.60* Alarm: Siren Toy High Low Tiny Speak 1.0 0:10 Alarm Alarm Siren 16 Bit / 48000 Hz 95091 Sounddogs Sound Library
11 Sounddogs Sound Library Sounddogs Alarm Sound Effects, Siren,Ambulance,In,Doppler,Old Sound Effects Waveform Siren,Ambulance,In,Doppler,Old.wav 4.40* Alarm: Siren Ambulance In Doppler Old 1.0 1:03 Alarm Alarm Siren 16 Bit / 48000 Hz 95081 Sounddogs Sound Library
12 Sounddogs Sound Library Sounddogs Alarm Sound Effects, Siren,Euro,Dist,Doppler,BG Sound Effects Waveform Siren,Euro,Dist,Doppler,BG.wav 3.50* Alarm: Siren Euro Dist Doppler BG 2.0 0:23 Alarm Alarm Siren 16 Bit / 48000 Hz 95083 Sounddogs Sound Library
13 Sounddogs Sound Library Sounddogs Alarm Sound Effects, Siren,High,Low,Small Speaker Sound Effects Waveform Siren,High,Low,Small Speaker.wav 2.60* Alarm: Siren High Low Small Speaker 2.0 0:10 Alarm Alarm Siren 16 Bit / 48000 Hz 95085 Sounddogs Sound Library
14 Sounddogs Sound Library Sounddogs Alarm Sound Effects, Siren,Toy,High,Low,BadSpeaker Sound Effects Waveform Siren,Toy,High,Low,BadSpeaker.wav 2.60* Alarm: Siren Toy High Low BadSpeaker 2.0 0:10 Alarm Alarm Siren 16 Bit / 48000 Hz 95090 Sounddogs Sound Library
15 Sounddogs Sound Library Sounddogs Alarm Sound Effects, Siren,Ambulance,High,Low,Old Sound Effects Waveform Siren,Ambulance,High,Low,Old.wav 3.50* Alarm: Siren Ambulance High Low Old 1.0 0:43 Alarm Alarm Siren 16 Bit / 48000 Hz 95080 Sounddogs Sound Library
16 Sounddogs Sound Library Sounddogs Alarm Sound Effects, Siren,Doppler,High,Low,French,2 Sound Effects Waveform Siren,Doppler,High,Low,French,2.wav 3.50* Alarm: Siren Doppler High Low French 2 1.0 0:31 Alarm Alarm Siren 16 Bit / 48000 Hz 95082 Sounddogs Sound Library
17 Sounddogs Sound Library Sounddogs Alarm Sound Effects, Siren,Fire Trucks 3,In,Horn Sound Effects Waveform Siren,Fire Trucks 3,In,Horn.wav 4.40* Alarm: Siren Fire Trucks 3 In Horn 2.0 1:04 Alarm Alarm Siren 16 Bit / 48000 Hz 95084 Sounddogs Sound Library
18 SoundStorm Library Sounddogs Alarm Sound Effects, Alarms-MultipleCarAlarms-Ex Sound Effects Waveform Alarms-MultipleCarAlarms-Ex.wav 3.50* Alarm - Multiple Car Alarm - Ext - Medium Close Up - Many Different Alarms @ Once, Honks, Sirens, Beeps 2.0 0:42 Alarm Alarm Siren 16 Bit / 48000 Hz 122007 SoundStorm Library
19 SoundStorm Library Sounddogs Alarm Sound Effects, Alarms-CarAlarms-Ext-CU-Mul Sound Effects Waveform Alarms-CarAlarms-Ext-CU-Mul.wav 3.50* Alarm - Car Alarm - Ext - CU - Multiple Alarms Set Off @ Once, Sirens, Honking, Beeping 2.0 0:40 Alarm Alarm Siren 16 Bit / 48000 Hz 121942 SoundStorm Library
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