The Siren Board

ThisTbolt sound "flat compared to thisTbolt. What causes this?

I get that the 1000 is single tone and the 1000t is dual but what causes this?
EDIT:Is this also why the ACA Hurricane 130 MKII sounds "raspy"

It has to do with the basic design of the siren. Rather than having radial ports and a self-aspirating rotor, a Thunderbolt forces pressurized air through a single narrow opening, giving it a harsher sound. When the blower is not running, they sound more like a conventional Model 2.

Daniel wrote:It has to do with the basic design of the siren. Rather than having radial ports and a self-aspirating rotor, a Thunderbolt forces pressurized air through a single narrow opening, giving it a harsher sound. When the blower is not running, they sound more like a conventional Model 2.

Ok, Thanks

It also depends on the blower. You can't hear the A1 blower over the siren usually but it gives it a very rhaspy sound. The 5M is somewhat louder but doesn't scream like the 4M does. It also as mentioned above depends on what chopper level it's on and what chopper is in it. Thunderbolts came with 3 chopper options the 5 (Right?), 4/5 and 5/6.

https://www.youtube.com/watch?v=NDIZHX7Tn3k Here is an example of a 1000T with the 6M. (Not my video) It's probably the smoothest thunderbolt I ever heard!

https://www.youtube.com/watch?v=3TjL2YHEEkc Here is a 1000T with the 5M. (Not my video) This wind down is no exception to how BA the thunderbolt is.

https://www.youtube.com/watch?v=k2QmGOZTgI4 (Ians video) a 1000 with a 6M. Notice how you can't hear the blower.

https://www.youtube.com/watch?v=btGnOr-OSPI A 1000 with the 5M. Notice that you can sort of hear the blower and it isn't as rhaspy as the other one. (Also ians video.)



EDIT: That 1000 video with the 6M isn't all that rhaspy... https://www.youtube.com/watch?v=Yeg78e4Y9G4 Try this one. (Not my video.)

Dang, that snow adds a effect to the video
Thanks, Coastal

Mmm hmm! Oh and to answer your other question no the hurricane doesn't sound rhaspy because of that. The hurricane is actually a 2 chopper siren with a 30 HP blower and a bigger siren head. So it's basically like 2 big single tone sirens with a lot of air. The hurricane comes with many different combinations of choppers instead of simply adjusting the frequency on the panel. The main reason it sounds so rhaspy on youtube is because it's loud (Distorting the camera) but from what I have heard they actually sound pretty smooth (or if they don't sound smooth it's because the 2 notes the choppers are making don't blend in a 1st note to 3rd note harmony.) but keep in mind I haven't heard one before. The hurricane and the thunderbolt I have come to discover aren't really comparable just because there are so many variables. Same as the T135 and the P50. Anyways my point is that there is going to be a little roar and a little different sounds coming out of them because they are truly different sirens. As mentioned above as well it's said the thunderbolt sounds like a model 2 without the blower... Well the model 2 is still a bit louder and the thunderbolt is a bit higher pitched but that is pretty dang accurate.

coastalsyrolover wrote:Mmm hmm! Oh and to answer your other question no the hurricane doesn't sound rhaspy because of that. The hurricane is actually a 2 chopper siren with a 30 HP blower and a bigger siren head. So it's basically like 2 big single tone sirens with a lot of air. The hurricane comes with many different combinations of choppers instead of simply adjusting the frequency on the panel. The main reason it sounds so rhaspy on youtube is because it's loud (Distorting the camera) but from what I have heard they actually sound pretty smooth (or if they don't sound smooth it's because the 2 notes the choppers are making don't blend in a 1st note to 3rd note harmony.) but keep in mind I haven't heard one before. The hurricane and the thunderbolt I have come to discover aren't really comparable just because there are so many variables. Same as the T135 and the P50. Anyways my point is that there is going to be a little roar and a little different sounds coming out of them because they are truly different sirens. As mentioned above as well it's said the thunderbolt sounds like a model 2 without the blower... Well the model 2 is still a bit louder and the thunderbolt is a bit higher pitched but that is pretty dang accurate.

Thanks. Does the Hurricane work well without the blower?

lilrags16 wrote:

coastalsyrolover wrote:Mmm hmm! Oh and to answer your other question no the hurricane doesn't sound rhaspy because of that. The hurricane is actually a 2 chopper siren with a 30 HP blower and a bigger siren head. So it's basically like 2 big single tone sirens with a lot of air. The hurricane comes with many different combinations of choppers instead of simply adjusting the frequency on the panel. The main reason it sounds so rhaspy on youtube is because it's loud (Distorting the camera) but from what I have heard they actually sound pretty smooth (or if they don't sound smooth it's because the 2 notes the choppers are making don't blend in a 1st note to 3rd note harmony.) but keep in mind I haven't heard one before. The hurricane and the thunderbolt I have come to discover aren't really comparable just because there are so many variables. Same as the T135 and the P50. Anyways my point is that there is going to be a little roar and a little different sounds coming out of them because they are truly different sirens. As mentioned above as well it's said the thunderbolt sounds like a model 2 without the blower... Well the model 2 is still a bit louder and the thunderbolt is a bit higher pitched but that is pretty dang accurate.

Thanks. Does the Hurricane work well without the blower?

No.

stormsetter4 wrote:

lilrags16 wrote:

coastalsyrolover wrote:Mmm hmm! Oh and to answer your other question no the hurricane doesn't sound rhaspy because of that. The hurricane is actually a 2 chopper siren with a 30 HP blower and a bigger siren head. So it's basically like 2 big single tone sirens with a lot of air. The hurricane comes with many different combinations of choppers instead of simply adjusting the frequency on the panel. The main reason it sounds so rhaspy on youtube is because it's loud (Distorting the camera) but from what I have heard they actually sound pretty smooth (or if they don't sound smooth it's because the 2 notes the choppers are making don't blend in a 1st note to 3rd note harmony.) but keep in mind I haven't heard one before. The hurricane and the thunderbolt I have come to discover aren't really comparable just because there are so many variables. Same as the T135 and the P50. Anyways my point is that there is going to be a little roar and a little different sounds coming out of them because they are truly different sirens. As mentioned above as well it's said the thunderbolt sounds like a model 2 without the blower... Well the model 2 is still a bit louder and the thunderbolt is a bit higher pitched but that is pretty dang accurate.

Thanks. Does the Hurricane work well without the blower?

No.

Not in the least bit.

lilrags16 wrote:ThisTbolt sound "flat compared to thisTbolt. What causes this?

I get that the 1000 is single tone and the 1000t is dual but what causes this?
EDIT:Is this also why the ACA Hurricane 130 MKII sounds "raspy"

The links don't work for me, so I'll assume that, as your post implies, you are indeed comparing the singe- to the dual-tone siren.

In a two-tone siren, depending on the ratio of ports, per rev you'll have certain a certain rate of maximum constructive phasing -where one upper port is approximately in step with the output of the port immediately beneath it- along with a minimum constructive phasing, where one port is mostly closed during the other's peak output. I think it's that wavering shift in phase at the chopper that is further intensified by the blown air cascading through the horn. Any time you get a ratio in which one number is not perfectly divisible by the other you'll get that expanding and contracting overlap that contributes to a resultant byproduct frequency, which probably explains as to why a dual-tone Thunderbolt sounds allot like a humongous dial tone.