Discussion of Outdoor Warning Systems
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The vibration really doesn't mean anything though. I've had SD-10's here vibrate the surrounding area, and they're pretty much the weakest siren we have. As for the actual sound output of the blowers, I've never heard anything but the 6M blowers on our Thunderbolts in person. Their sound output was in all honesty comparable to a Cyclone to my ears(we have both here and I've heard both, and several units from the same distance). I'm sure they were louder by a couple DB but the difference wasn't noticeable to me. I'm sure with that in mind the difference between a 4, 5 or 6M isn't that significant, again, at least to me. You can only force so much air through a hole the size of a sharp key on a piano. The size of blower used does seem to affect the tone of the siren to some degree though, at least judging by videos of TBolts with different sizes.coastalsyrolover wrote: ↑Thu May 11, 2017 3:17 pmI don't think the vented covers would fit a 5 or 6M... 4Ms are pretty loud though... I know the 4 M single tone bolt I recorded a while back shook the parking lot I was in... and it was pretty high up.
I didn't say i judge the volume of sirens based on videos, i said i can judge the tone to an extent. It's the only way I've been able to hear any difference the blowers make in the sirens sound. Like i said I've only heard 6M thunderbolts in person.coastalsyrolover wrote: ↑Thu May 11, 2017 8:36 pmWell and I'm sure it depends on the chopper used, how well the blower actually runs, etc... etc... remembering that for most humans to hear a difference in volume, the volume is usually 3 DB variance. However no human is alike and there is speculation that some of us perceive sound differently. The STL-10 I heard didn't seem to rattle anything or really bother my ears at all (almost there though... like maybe an "inch" louder and it'd have distorted my hearing...) and the 2001 ever slightly distorted it while the bolt completely did when it pointed at me. BUT! I've been exposed to a lot of loud noises... so perhaps my ears are more used to (or sadly worn down on) certain frequencies. When talking about the blowers members here have measured them and found a 2-3 fb difference same as the difference between single and dual tone (because dual tones A: cancel and B: you are almost forcing air through 2 tiny holes instead of one big one.) and also let's not forget the buzzing. The part of this video I watched the siren wasn't rotating so I couldn't really get a good bearing on the buzz. But I tell you it certainly didn't sound like a 6M so that's off my list. The 5M has a deeper more rattle like buzz or so I hear anyway... so with the vents and the buzzing led me to that conclusion... oh and also I wouldn't judge siren volumes on videos... in every siren video i have taken the camera mic leveled the sound. (That's why I sometimes talk in my videos... but sometimes that volume gets all messed up too...)
Jeb told me that he's slapped 4M covers on 5M blowers before, though I might have misunderstood himcoastalsyrolover wrote: ↑Thu May 11, 2017 3:17 pmI don't think the vented covers would fit a 5 or 6M... 4Ms are pretty loud though... I know the 4 M single tone bolt I recorded a while back shook the parking lot I was in... and it was pretty high up.
6M blowers were never used on 1003s anywaycoastalsyrolover wrote: ↑Thu May 11, 2017 8:36 pmWell and I'm sure it depends on the chopper used, how well the blower actually runs, etc... etc... remembering that for most humans to hear a difference in volume, the volume is usually 3 DB variance. However no human is alike and there is speculation that some of us perceive sound differently. The STL-10 I heard didn't seem to rattle anything or really bother my ears at all (almost there though... like maybe an "inch" louder and it'd have distorted my hearing...) and the 2001 ever slightly distorted it while the bolt completely did when it pointed at me. BUT! I've been exposed to a lot of loud noises... so perhaps my ears are more used to (or sadly worn down on) certain frequencies. When talking about the blowers members here have measured them and found a 2-3 fb difference same as the difference between single and dual tone (because dual tones A: cancel and B: you are almost forcing air through 2 tiny holes instead of one big one.) and also let's not forget the buzzing. The part of this video I watched the siren wasn't rotating so I couldn't really get a good bearing on the buzz. But I tell you it certainly didn't sound like a 6M so that's off my list. The 5M has a deeper more rattle like buzz or so I hear anyway... so with the vents and the buzzing led me to that conclusion... oh and also I wouldn't judge siren volumes on videos... in every siren video i have taken the camera mic leveled the sound. (That's why I sometimes talk in my videos... but sometimes that volume gets all messed up too...)