Analog Siren Controllers

[Traxstar1825]

Does anyone know how analog speaker siren controllers work? Like I assume digital ones just play a sound file, but what makes a siren controller analog? Also I saw a video of a Whelen analog siren with low battery’s and it’s pitch went all over the place. What causes this?

[Tyler]

Analog controllers basically generate their own tones using direct current. A full analog controller, like the SiraTone or early Alertronic ESC controllers use oscillators and such to generate the sounds and runs them through various buffers to get to the full signal output ready for amplification.

Digital controllers by contrast are computers that typically take an instruction set and generate the tones and push it through a digital to analog converter(DAC). Some other digital systems like ones from ATI, just play audio files and run it through a DAC.

A hybrid system like the analog ESC-864 or Federal MC controller use a computer to control everything, but the tone generation is done using analog circuits controlled by the computer.


Hopefully these basic descriptions are helpful!

[Traxstar1825]

Analog controllers basically generate their own tones using direct current. A full analog controller, like the SiraTone or early Alertronic ESC controllers use oscillators and such to generate the sounds and runs them through various buffers to get to the full signal output ready for amplification.

Digital controllers by contrast are computers that typically take an instruction set and generate the tones and push it through a digital to analog converter(DAC). Some other digital systems like ones from ATI, just play audio files and run it through a DAC.

A hybrid system like the analog ESC-864 or Federal MC controller use a computer to control everything, but the tone generation is done using analog circuits controlled by the computer.


Hopefully these basic descriptions are helpful!

Yes it was very helpful! So is there anything mechanical going on inside the cabinet? Forgive me for my lack of knowledge on electronic sirens lol.

[Traxstar1825]

Also, if anyone has a picture of the inter workings of one of these cabinets I am very curious on how they are laid out.

[Tyler]

Yes it was very helpful! So is there anything mechanical going on inside the cabinet? Forgive me for my lack of knowledge on electronic sirens lol.

Typically the only thing mechanical inside the controllers is a relay to activate the rotator on rotating arrays, but on controllers like ACA/ASC's controllers, they use a relay to engage the amp deck, hence why those sirens windup softly and then suddenly blast at full power.

Also, if anyone has a picture of the inter workings of one of these cabinets I am very curious on how they are laid out.

Which controller would you like to look at?

[Traxstar1825]

Yes it was very helpful! So is there anything mechanical going on inside the cabinet? Forgive me for my lack of knowledge on electronic sirens lol.

Typically the only thing mechanical inside the controllers is a relay to activate the rotator on rotating arrays, but on controllers like ACA/ASC's controllers, they use a relay to engage the amp deck, hence why those sirens windup softly and then suddenly blast at full power.

Also, if anyone has a picture of the inter workings of one of these cabinets I am very curious on how they are laid out.

Which controller would you like to look at?

Oh okay, I’ve always inserted why ASCs did that. And I guess any analog cabinet. The only pictures I can find are of the controls

[Ohio_Man]

Typically the only thing mechanical inside the controllers is a relay to activate the rotator on rotating arrays, but on controllers like ACA/ASC's controllers, they use a relay to engage the amp deck, hence why those sirens windup softly and then suddenly blast at full power.

I always thought that the soft windup/hiss was some kind of life extension thing. Like a soft start or star/delta starters for an electric motor.