Pics from various internet locations

[fstbolt]

This is just a collection of pics I found on google.

Thunderbolt:


Looking up on a WPS-2905:


Sentry 20V2T:


(I think): Hormann Siren:


DSA in Hilo,Hawaii:


2t22 in Hawaii:


WPS-4004:

[kswx29]

Maybe you should search before you post. One of these topics is yours!
http://www.airraidsirens.com/forums/vie ... php?t=2828
http://www.airraidsirens.com/forums/vie ... php?t=2789

[loudmouth]

thanks for posting things we can look up on our own....

[fstbolt]

Hey, Im just trying to donate something to the community.
althoug 2t22boy is right i should have looked.

[va_nuke_pe]

It looks like Madahcom SPT-2117's mounted side by side to me. These are "Giant Voice" outdoor loudspeakers.

[Robert Gift]

thanks for posting things we can look up on our own.... :roll:

I like new posts of things I would not have known to look for.
Never saw that Hormann before.
I question the efficiency of their speaker design.
Seems also that the speakers should be rotated 90 degrees.

[SirenMadness]

Oh, believe me, with the efficiency of Hormann's designs, you'd put your questioning on whoever installed their sirens instead!
Those speakers are extremely efficient; it is simply the arrangement that does not look that way.

[Robert Gift]

I believe there will be unnecessary cancellation caused by the parallel speakers.

It also appears that rarther than have longitudinal spread, they have it vertical.

Better speaker placement and orientation would lessen cancellation.

Why are no speakers facing the other two directions?

[JasonC]

I believe there will be unnecessary cancellation caused by the parallel speakers.

Quite the opposite...if they are phased right, they will compliment each other. Hormann engineers designed them this way. Coverage is claimed to be nearly equal throughout 360 degrees.

[va_nuke_pe]

To answer your questions:

1. They are LOUDSPEAKERS, not sirens. Being directional is very desirable for LOUDSPEAKERS, not so much for sirens.

2. When they generate a tone (imitating a siren), believe it or not, they behave as omni-directional devices beyond about 200 feet away.

3. The purpose of the "somebody ran a car over the bugle" stacked horn design is to limit attenuation loss in the near field and thereby bump up range slightly - stacked, narrow beam arrays have a 3 dB/DD divergence loss, not the normal spherical divergence loss of 6 dB/DD (decibels per distance doubled) from traditional horns.

These look like Madahcom SPT-2117 speaker arrays - I am not aware that Hormann manufactures anything like this design, although they could be a reseller.