I can't remember what is the BP100. Smaller totally round projector? Are the bullet sirens with long cones CP 100s? All drivers are 100 watt. For 200 watt they just have two 100 W drivers in the speaker unit. Also, we have a "Y" connecting two 100 watt drivers to one cone/projector, but tw...

I too have observed that phenomenon when listening to the various siren videos w/ dual tone sirens (the T-bolt in particular). And yes, you can simulate lower tones by combining two other tones. Take for example, the pipe organ. Play the C1 (let's say the C1 of this organ is around 32.5 Hz) and the ...

Blue light is more noticeable to the human eye than red. Also stands out in background which is often red and clear lights. Incandescents, even halogen, do not produce blue well. LEDs blues are so rich and pure. We only have red LEDs. Blues are too expensive. Our LEDs have a clear case and black bac...

I heard an Aurora, CO truck responding with Q sounding. Suddenly, nothing. They must have hit something that instantly stopped and destroyed the siren. They are mounted on the left front bumper. Later, I learned of the new eQs and that Aurora had replaced some q2bs. They had clicked off the siren wi...

In designing sirens, is the purpose of two tones to produce a "resultant" tone"? With two tones sounding simultaneously, their sound waves will add (reinforce) and subtract (cancel) at various frequencies. For example: sounding an E-natural and a G-natural (a perfect minor third above...

Haven't heard one since the 60's. Saw one in a collector's old Cadillac Ambulance a few weeks ago. They really screamed and were high-pitched, I recall. Think everything has gone to electronic and Q2bs. I like electronic because they can ask drivers to move out of the way. (Never TELL someone to do ...

We have an LED Opticom-like emitter on our vehicle. The Good: It will cycle crosstraffic and opposing traffic signal Green-Yellow-Red just like a signal change. Then give the traffic ahead of the Emergency Vehicle a green thru signal, and green arrows if any. This allows traffic ahead to get moving ...

In Lewistown, PA, in late 50s, as a little boy I asked my grandfather what turned on the "Mee-Mool" lights. Pup-pup said the weight of the train squeezed the "juice" out of the rails. So, I started piling ballast rocks on the rails, then finally thought to stand on a rail since I...

Dear Soundoff, What is that monstrosity in your photo? An engine-powered Victory siren? Looks like 2 2t22s stacked but an air intake would be necessary between them. What a fun and a memorable story getting busted. Are those 2001s for tornado warning or escape? I enjoyed your links that I was able t...

The siren is described as horizontal with a rotor\stator at each end. (Wouldn't it be funny if it were the same Amercian make as my father's McCandless Township, PA volunteer FD?) (Sorry, I have not yet learned all the makes/models.) Now, my brother-in-law, a member of the Communist Party, plans to ...