The role of the siren is crucial. This is to get the attention of pedestrians and drivers to pay attention to police cars on the road. As such, they can give way as needed and be used in a variety of everyday and emergency situations. They are vital to clearing the road in an emergency, and a siren heard on the road should tell pedestrians not to cross the road because a police car is approaching.
More than one siren
The different sounds of a police siren, fire truck siren or ambulance siren may not be so noticeable to the average person. After all, to them, it's just noise. However, for the police who operate these sirens, the difference between these noises is not only notable, but important. Different purposes and situations have different siren sounds.
Below, we will describe the different siren sounds and how they are used.
different types of sirens
It's worth noting that technically there is no difference between the individual voices. Yes, there are different sounds that are identifiable, and you may have seen people debating whether the siren most often used by the police should be "nee-nah" or "woo-woo". However, police vary the way they use their sirens as needed by the situation, and there are several different types of note.
cry
It's a sound that alternates quickly between high and low pitches, one of the two most readily available commands in most siren command boxes. It is often used in conjunction with rapidly flashing emergency lights to quickly grab the attention of the driver in front of the car. In most cases it means "stand aside", and urban areas often use shorter yelps (compared to longer wails). This is because short-duration sounds are thought to bounce off walls better, making them easier to hear in cities.
wail
Like yelp, the wail alternates between highs and lows, but it's much slower. This is another command frequently used in most siren command boxes. Likewise, it is often used in conjunction with flashing emergency lights. Compared with the shouting of "Woohoohoo", the sorrow is longer, and it is even longer. , in these environments, longer, longer sounds travel better and are less suitable for urban use.
high and low
hi-lo is very different from yelp and wail sirens. It doesn't have a "woo" sound but an "ee-oo-ee-oo" sound, not as fast or urgent as the others. It is also known as the "European style" siren because it is frequently used by emergency services on the continent. hi-lo is generally used for the same purpose as yelp and wail. However, it is used less frequently.
In addition, the three different siren functions on most control panels are also suitable for situations where there is more than one emergency vehicle on the road. This lets pedestrians and drivers know that there are several vehicles on the road they should pay attention to, even after the first one or two has passed.
power call
The power call is a siren sound, much less than the three mentioned above. It's a monotonous "woo-woo-woo-woo-woo" sound that doesn't change with pitch or pitch. It's less frequently used simply because it was the first-ever electronic siren call, and has been replaced by wailing, shouting, and high-pitched sounds.
whistle
A siren is a long, piercing sound that rises rapidly in pitch and volume, then falls slowly and becomes quiet again. It's not used as often as other sounds on modern siren control panels, but some cars can still use it when equipped. For one thing, it's not electronic like any of the other sounds mentioned here, but rather pneumatically driven. So if the electronic system fails to work for some reason, the whistle can still be used. Also, it's a very unique and noticeable sound, so it can still be used as a siren.
perforator
The siren sounded a lot like the scream when it was first heard. In fact, it serves much the same purpose, as most siren operators find it more effective in smaller urban spaces, especially in heavy traffic. However, when listening carefully, it's much faster and therefore sounds more urgent. Likewise, if other vehicles on the road are already using Yelp, it can be used to help the user's vehicle stand out.
howling
The howl sounds a lot like a wail, but the lower notes on this siren play a distinct sound below the main note. This is a low frequency sound designed for vehicles directly in front of a police car. As such, it is considered particularly useful in clearing the way for passing traffic in high-speed pursuits or emergencies. Since the driver can hear and feel the siren, they can move out of the way more easily.
