I get my hearing checked every 2 years for work, so I know it's not me, but has the volume of the sirens on emergency vehicles been turned down or is it that cars have become more sound proof. Once upon a time you would be able to hear the siren from miles away, now I notice the lights first and still not necessarily hear the sirens until they are maybe a few car lengths away. I do have MTZs on my car so there is probably a fair bit of road noise than normal, but driving my wife's car yesterday, a iX35, I thought the same thing when a cop car came screaming by (and no, the radio wasn't turned up loud)
The other thing I noticed for the first time, was when the police car came up behind some cars stopped at some traffic lights he turned the siren and lights off and waited patiently. Once the lights turned green, the lights and siren came back on and he was off. I could only assume that was to avoid pressuring the car in front to 'run' the red light. 
Cars are more sound proof now than they used to be and most drivers dont seem to be aware that there is more to the world around them than those few meters in front of the bonnet.
We are a big red truck flashing lights sirens and a loud as f@#$ air horn and people still dont get out of our way or notice us.
When they do the first thing they do is slam there foot on the brake and make us lose all momentum before they finally move over and let us past.
At traffic lights we are not allowed to push people into running a red. Its nice if they can creep forward onto the pedestrian path and clear some room but have seen far to many people just blindly nail it across an intersection thinking they are doing the right thing to let us through. So thats why if there is no way some one can safly make space we will turn the sirens off so it takes the pressure off those cars sitting at the front of the line so they wont risk running the red and causing accidents.
Yep, police and ambulance here sound quieter and Im considering as a pedestrian.
A slight aside, I personally think it was a huge mistake allowing different sirens to be used, IMHO, all police cars should use the same lights and sirens, all ambulance the same and all firetrucks also. Dont care if there is a different sound for each service but it just seems wrong to allow a service to have multiple sounds depending on who manufactured the particular unit. I know this sounds a bit pedantic, but it's easier to condition a response to a situation if these things are consistent. It would also help minimise confusion when the radio plays a sirens in a song etc.
I think I've noticed them turning off the sirens more, and flicking them on for intersections/ busy parts of the road.
Siren aren't getting quieter.. It the sound proofing of cars.
Emergency Vehicle Warning systems are all very similar and I think there is an Australian Standard for them somewhere. Generally all have the yelp, pulse and wail tones, each having differing penetrating abilities, hence the reason emergency vehicles change tones when approaching an intersection etc.
B
Select to expand quoteToph said..
The other thing I noticed for the first time, was when the police car came up behind some cars stopped at some traffic lights he turned the siren and lights off and waited patiently. Once the lights turned green, the lights and siren came back on and he was off. I could only assume that was to avoid pressuring the car in front to 'run' the red light.
Correct... The cops were showing good form. It's pointless screaming up to a blocked intersection with sirens blazing and pressuring people to move and potentially cause more issues than you were initially responding too.
Generally the worst "bad form" offenders I see are the ambos, but I think that comes down to lack of EV training..
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We all used to have our windows down to stay cool. Now with our air conditioning on, we all have our windows closed to stay cool.
Davage and Crackas are on to it. There is a huge responsibility attached to having endorsement to drive under EVS. To put it simply - it allows others to know that you are breaking the road laws. A skilled driver will use the yelp and siren functions carefully and so as not to put pressure on drivers or alarm pedestrians (you will notice many turn sirens off near schools).
As far as sound goes - try standing next to a truck in the shed when someone accidentally switches the siren on whilst cleaning the cab and you'll realise that they haven't turned the sound down.
Thanks for the responses. I had thought a bit along the same lines as Harrow. My current car (which I've had now for 10 odd years) is the first car I've had with working air-conditioning, so as Harrow said, the windows are now usually up. That being said, I wouldn't of been surprised if OHS got onto it and turned down the volume as well.
What gets me is the radio stations and songs using sirens or something similar, as soon as I here them I turn the radio down check my mirrors, put the windows down and nothing is there. Annoys the **** out of me.
Very surprised with all the bluetooth and WiFi they don't interconnect and emit a warning for emergency services/vehicles.
About 20 years ago a bloke invented a transmitter that went on emergency vehicles that put out a radio signal on all frequencies for a defined area that would alert drivers but it never took off.. Not sure the reasons why, I thought it was a good idea at the time.
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Select to expand quotecrakas said..
About 20 years ago a bloke invented a transmitter that went on emergency vehicles that put out a radio signal on all frequencies for a defined area that would alert drivers but it never took off..
I remember something like this on an Inventors / Catalyst / Quantum / Towards 2000 style TV show ages ago. [pre FM radio]
A really high powered radio signal that over-rode any radios within a few hundred yards.
IIRC, it was powerful enough at very short ranges that it could even be heard through the speakers of a radio that was turned off.
I never could understand how they managed to get short range with such a high power output though.
stephen
Select to expand quotesn said..crakas said..
About 20 years ago a bloke invented a transmitter that went on emergency vehicles that put out a radio signal on all frequencies for a defined area that would alert drivers but it never took off..
I remember something like this on an Inventors / Catalyst / Quantum / Towards 2000 style TV show ages ago. [pre FM radio]
A really high powered radio signal that over-rode any radios within a few hundred yards.
IIRC, it was powerful enough at very short ranges that it could even be heard through the speakers of a radio that was turned off.
I never could understand how they managed to get short range with such a high power output though.
stephen
The only way I can think of is if the transmitter transmitted on the IF frequency, which is the frequency that the radio signal is brought down to before being turned into audio. Please, anybody that actually understands it, forgive my really dodgy recall of how AM radio receivers work.
Select to expand quotesn said..crakas said..
About 20 years ago a bloke invented a transmitter that went on emergency vehicles that put out a radio signal on all frequencies for a defined area that would alert drivers but it never took off..
I remember something like this on an Inventors / Catalyst / Quantum / Towards 2000 style TV show ages ago. [pre FM radio]
A really high powered radio signal that over-rode any radios within a few hundred yards.
IIRC, it was powerful enough at very short ranges that it could even be heard through the speakers of a radio that was turned off.
I never could understand how they managed to get short range with such a high power output though.
stephen
Yeah...that's the one. Thinking it was not quite 20 years ago but close to it..
