Jersey Village getting Sentry VR sirens?

[SirensOfNewYork]

https://www.twdb.texas.gov/publications ... dacted.pdf
Upon browsing the internet for sirens in Texas, I found this document which is about Jersey Village, Texas, getting a flood/storm siren. It appears to be a Sentry VR series siren, which I thought was interesting.

[Taterworks]

The siren is already there - it's on Google Street View at 7960 Senate Ave, at the south end of Carol Fox Park.



Now you know what to do - someone near Houston go get us a recording.

Because it's a HyperSpike MA-2 emitter, it barely looks like anything, so you'll have to keep an eye out for the pole boxes.

[SirensOfNewYork]

The siren is already there - it's on Google Street View at 7960 Senate Ave, at the south end of Carol Fox Park.



Now you know what to do - someone near Houston go get us a recording.

Because it's a HyperSpike MA-2 emitter, it barely looks like anything, so you'll have to keep an eye out for the pole boxes.

Yes! I'd love to see those in action.

[jacob585]

That is a lot tinier than in the advertising pictures on the site.

[SirensOfNewYork]

That is a lot tinier than in the advertising pictures on the site.

Much. I was a little taken aback. But I guess quality>size.

[Taterworks]

That is a lot tinier than in the advertising pictures on the site.

Much. I was a little taken aback. But I guess quality>size.

So the spec sheet value of 148dB from the HyperSpike web site is a figure measured at 1 meter, which is the standard measurement distance for loudspeakers. But the standard measurement distance for outdoor sirens is 100' (~30 meters). At that distance, the MA-2 makes a very respectable 118 dB. Even though it is not as loud as many larger sirens, it still makes a lot of noise especially for something its size, considering that it has no horns - it's an array of cone speaker drivers with weatherproof coating for direct exposure to the elements. This is part of how it is able to produce excellent sound quality and intelligibility; resonance and distortion mechanisms of horns are not present, even though the resulting system is a lot less power-efficient; the HyperSpike emitters need quite a bit of power to make full rated SPL.

[DJ2226]

That is a lot tinier than in the advertising pictures on the site.

Much. I was a little taken aback. But I guess quality>size.

So the spec sheet value of 148dB from the HyperSpike web site is a figure measured at 1 meter, which is the standard measurement distance for loudspeakers. But the standard measurement distance for outdoor sirens is 100' (~30 meters). At that distance, the MA-2 makes a very respectable 118 dB. Even though it is not as loud as many larger sirens, it still makes a lot of noise especially for something its size, considering that it has no horns - it's an array of cone speaker drivers with weatherproof coating for direct exposure to the elements. This is part of how it is able to produce excellent sound quality and intelligibility; resonance and distortion mechanisms of horns are not present, even though the resulting system is a lot less power-efficient; the HyperSpike emitters need quite a bit of power to make full rated SPL.

Sentry rates them at 120 dB. I think one thing that should be pointed out is that the rating isn't produced in the same way for the VR as sirens typically are. Usually sirens are set up and ran in alert for the full SPL. This is for both mechanical and electronic siren. Whelen did this with their sirens and took the pitch up to 560 Hz to squeeze a little more performance out of them, and this resulted in roughly a 2-3 dB increase on pretty much all of the sirens. This allowed the 4004 and 2910 to reach 129 dB, and had the 4008 still been on the market it would be up to roughly 132 dB like the T-135 AC/DC.

With that said Sentry's tones don't inspire much confidence. Their alert tone peaks at 800 Hz. That's a little on the high side, and it's kind of ironic given that they pride themselves, rightly so IMO, on the low pitch of their sirens. If they dropped it down a bit and tweaked it the way Whelen did they probably could push slightly more SPL out, but more importantly they could achieve greater range. From what I gather in the document the controller is limited to either four tones, voice announcements, or a combination of the two. It's looking like a slimmed down version of an LRAD, and I feel like that was the direction they wanted to take it as it would be mainly for voice coverage. For weather alerts you really only need a handful of voice announcements and live PA. I kinda wish I could experiment with the serial port on their controller and interface it with something like an Arduino using RS232. The one I seen in person had at least 3 sections for serial headers. I've built a tone generator with an Uno that would work wonders with that speaker.

[SirensOfNewYork]

Much. I was a little taken aback. But I guess quality>size.

So the spec sheet value of 148dB from the HyperSpike web site is a figure measured at 1 meter, which is the standard measurement distance for loudspeakers. But the standard measurement distance for outdoor sirens is 100' (~30 meters). At that distance, the MA-2 makes a very respectable 118 dB. Even though it is not as loud as many larger sirens, it still makes a lot of noise especially for something its size, considering that it has no horns - it's an array of cone speaker drivers with weatherproof coating for direct exposure to the elements. This is part of how it is able to produce excellent sound quality and intelligibility; resonance and distortion mechanisms of horns are not present, even though the resulting system is a lot less power-efficient; the HyperSpike emitters need quite a bit of power to make full rated SPL.

Sentry rates them at 120 dB. I think one thing that should be pointed out is that the rating isn't produced in the same way for the VR as sirens typically are. Usually sirens are set up and ran in alert for the full SPL. This is for both mechanical and electronic siren. Whelen did this with their sirens and took the pitch up to 560 Hz to squeeze a little more performance out of them, and this resulted in roughly a 2-3 dB increase on pretty much all of the sirens. This allowed the 4004 and 2910 to reach 129 dB, and had the 4008 still been on the market it would be up to roughly 132 dB like the T-135 AC/DC.

From what I gather in the document the controller is limited to either four tones, voice announcements, or a combination of the two.

What are the possible tones?

[Taterworks]

Much. I was a little taken aback. But I guess quality>size.

So the spec sheet value of 148dB from the HyperSpike web site is a figure measured at 1 meter, which is the standard measurement distance for loudspeakers. But the standard measurement distance for outdoor sirens is 100' (~30 meters). At that distance, the MA-2 makes a very respectable 118 dB. Even though it is not as loud as many larger sirens, it still makes a lot of noise especially for something its size, considering that it has no horns - it's an array of cone speaker drivers with weatherproof coating for direct exposure to the elements. This is part of how it is able to produce excellent sound quality and intelligibility; resonance and distortion mechanisms of horns are not present, even though the resulting system is a lot less power-efficient; the HyperSpike emitters need quite a bit of power to make full rated SPL.

Sentry rates them at 120 dB. I think one thing that should be pointed out is that the rating isn't produced in the same way for the VR as sirens typically are. Usually sirens are set up and ran in alert for the full SPL. This is for both mechanical and electronic siren. Whelen did this with their sirens and took the pitch up to 560 Hz to squeeze a little more performance out of them, and this resulted in roughly a 2-3 dB increase on pretty much all of the sirens. This allowed the 4004 and 2910 to reach 129 dB, and had the 4008 still been on the market it would be up to roughly 132 dB like the T-135 AC/DC.

With that said Sentry's tones don't inspire much confidence. Their alert tone peaks at 800 Hz. That's a little on the high side, and it's kind of ironic given that they pride themselves, rightly so IMO, on the low pitch of their sirens. If they dropped it down a bit and tweaked it the way Whelen did they probably could push slightly more SPL out, but more importantly they could achieve greater range. From what I gather in the document the controller is limited to either four tones, voice announcements, or a combination of the two. It's looking like a slimmed down version of an LRAD, and I feel like that was the direction they wanted to take it as it would be mainly for voice coverage. For weather alerts you really only need a handful of voice announcements and live PA. I kinda wish I could experiment with the serial port on their controller and interface it with something like an Arduino using RS232. The one I seen in person had at least 3 sections for serial headers. I've built a tone generator with an Uno that would work wonders with that speaker.

The similarity to an LRAD type of product (a ruggedized sound emitter for military use) isn't just coincidence; HyperSpike is a brand of Under Sea Sensors, Inc., a company in northeast Indiana (Columbia City, near Fort Wayne) which is part of a UK-based defense conglomerate called Ultra Electronics; their main business is sonar buoys for maritime antisubmarine applications. I know a couple of the people who are involved there. Their principal product is the HyperSpike "acoustic hailing" products, which use a reflector geometry called a HyperSpike (like a dish reflector except inverted so the peak is in the center) to collimate the output from multiple horn-loaded compression drivers.

The MA-series outdoor mass notification speakers are a different sort of design; they don't use any horn loading at all. Instead, they use efficient cone loudspeakers (able to be packaged in a much smaller system and without some of the drawbacks of acoustic horns) and emit sound through 360 degrees using five arrays of drivers. The speaker cones are paper, but they have a coating on the outside surface that repels water. They were originally sold for portable mass notification systems on military bases, and distributed through a number of companies, along with the Encompass(tm) pre-built electronic cabinets, but it looks like Sentry Siren is purchasing the emitters only, and using their own electronics (just my guess based on the description in the article).