Discussion of Outdoor Warning Systems
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I agree, the T-128 does have a deeper tone even though the RM-130 and the T-128 both use 8-port choppers. It's because the T-128's motor runs at a slower RPM than the RM-130 and deeper tones carry out father than higher-pitched ones (and can penetrate walls).AST128_RyanK wrote:I live between two siren locations: one RM-130 and another T-128. I have found that the T-128s deeper tone is far louder compared to the RM-130s softer tone. Although I don't know if the age of the siren has to do with this. The T-128 is practically brand new having replaced a older T-128 witch had a broken motor three years ago. The RM-130 is apart of the original system which was installed back in the 1990s.
Weird. Always thought they were 8-port, sure sounded like it... Well, you learn something new every day!SuperBanshee wrote:The RM-130 uses a 9 port rotor with 9 horns extending out of its stator. In my experience the RM-130's general sound range is very close to a T-128, however it is higher pitched and produces a more shrill sound. At long distance, the sound becomes less shrill and mellows out considerately.
The RM-130's pitch (580-600 hertz) is more consistent than the T-128, which jumps anywhere between 435 and 560 hertz.
I grew up in the city of Fond du Lac which used both types of sirens. It was a good opportunity to study both sirens individually, although I've lost count of how many sirens they really used. There must have been at least 9 RM-130s and 4 T-128s with another 2 T-128s in neighboring North Fond du Lac.
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Midland, MI is the same way, all we have are the two types of sirens. But yes I would agree the RM-130 loses its "punch" the farther you get from it. During most activations of the sirens I have found the the T-128 more audible than the RM-130s. I use T-128 singularly becuase it's surrounded by RM-130s in all directions. The most T-128s are located in the Southern portion of the system, in the county.SuperBanshee wrote:The RM-130 uses a 9 port rotor with 9 horns extending out of its stator. In my experience the RM-130's general sound range is very close to a T-128, however it is higher pitched and produces a more shrill sound. At long distance, the sound becomes less shrill and mellows out considerately.
The RM-130's pitch (580-600 hertz) is more consistent than the T-128, which jumps anywhere between 435 and 560 hertz.
I grew up in the city of Fond du Lac which used both types of sirens. It was a good opportunity to study both sirens individually, although I've lost count of how many sirens they really used. There must have been at least 9 RM-130s and 4 T-128s with another 2 T-128s in neighboring North Fond du Lac.
CIMG0239.JPG
Yes. Things like the wind can actually push the noise a siren creates. Things like humidity ambient noise can dampen their sound at times.AST128_RyanK wrote: Weirdly though, and I don't know if any other siren enthusiasts have expirenced this but the loudness of the sirens ambiance varies from test to test. Sometimes it's very clear and loud, and other times it's softer and quite. I experienced a quieter test today. Would atmospheric conditions play a role in this?
Well that answers what I have been curious about for the past several years, thank you.DJ2226 wrote:Yes. Things like the wind can actually push the noise a siren creates. Things like humidity ambient noise can dampen their sound at times.AST128_RyanK wrote: Weirdly though, and I don't know if any other siren enthusiasts have expirenced this but the loudness of the sirens ambiance varies from test to test. Sometimes it's very clear and loud, and other times it's softer and quite. I experienced a quieter test today. Would atmospheric conditions play a role in this?