| Air horns are devices used to create a very loud | | | | The diameter of the air inlet can change the decibel |
| noise. They have been used in many places as a | | | | level of the output sound, while the internal components |
| warning device, fire trucks, ambulances, and even | | | | and the material used to create the bell horn can |
| ships. The train air horn is a version of air horns that is | | | | cause a change in the tone of the sound. But what |
| used on trains. Originally, the horns used on trucks and | | | | can make a really big difference is the size and shape |
| trains were the same, i.e. produced the same sound. | | | | of the train air horn, both of which cause a significant |
| This created some confusion, eventually culminating in | | | | change in the tone. The power that train air horns used |
| a tragic accident in which a driver mistook a train to a | | | | come from an installed air supply tank. The air supply |
| truck after hearing the horn, clearly showing the need | | | | tank in turn is refilled using a pump, which can use any |
| for trains to have a unique horn. From then on, trains in | | | | fuel such as diesel. The system needs a lot of air, and |
| many developed cities began to have at least two | | | | consequently there should be a provision for storing |
| horns forming the air horn, that both sound at the | | | | enough of whatever fuel it uses in order to maintain a |
| same time, creating a chord. | | | | constant supply. |
| The train air horn sounds what is called a minor | | | | Train air horns used to be made out of various metals, |
| seventh chord, which is louder than the major chord | | | | but currently they are made out of chrome and brass |
| that is sounded by normal truck horns. The train blows | | | | for aesthetic purposes, as this attracts more |
| these horns in certain recognized sequences that are | | | | customers. In the recent past, there has been a |
| pre-determined for different situations, e.g. at a grade | | | | growing trend of using train air horns on personal cars |
| crossing. The train air horn can be thought of as a | | | | and trucks, albeit ones with a lower output of sound. |
| type of speaker that pushes air out. It has a | | | | This has seen an increase in their popularity (in fact the |
| diaphragm, which opens and shuts quickly due to this | | | | companies that previously produced them purely on |
| air pressure, several times in one instant. The speed of | | | | order are now retailing them publicly), although the |
| this happening creates the loud stead sound. There are | | | | motives for this use are still questionable. However the |
| different types of train air horns, each of which has | | | | train air horn as used on locomotives still maintains its |
| their own pitch due to differences in many factors. | | | | unique sound to ensure safety. |