Siren, horn, bell and screamer terminology

[mb2]

Working from the Bosch documentation, would I be correct in saying that 'siren' or 'horn' always refers to the outdoor noise maker and is normally driven by a square wave of varying frequency from the control panel?

Does 'bell' or 'screamer' always refer to the indoor noise maker and is it always driven by a constant voltage?

Is the bell/screamer assumed to be a piezo with its own driver circuit?

[madtech]

To be strictly correct:-
Horn = a horn shaped speaker. This is driven by an oscillating voltage from the control panel, think of it like an ugly speaker from your home sound system
Siren = similar to the above, but driven by a DC power source.
Screamer = Is typically a top hat or recess mounted piezo electric screamer, driven by a DC power source same as the Siren above
Bell = Is commonly used as another term for siren, however strictly speaking is a physical bell with a mechanical hammer that is used to impact the bell to make the noise. Typically driven by DC.

[mb2]

The SC03 horn that came with my kit has the lopsided weight you typically associate with a magnet/voice coil assembly.

When shopping online, if it looks like a horn and doesn't mention piezo, do you assume that it's a magnet/voice coil system?

[secure]

Some siren kits come with a horn/siren combo unit, if it's just horn you need use the horn wiring or if panel puts out 12v use the siren wiring terminals.

Bosch panels are horn output.

[mb2]

Some siren kits come with a horn/siren combo unit, if it's just horn you need use the horn wiring or if panel puts out 12v use the siren wiring terminals.

Bosch panels are horn output.

You got me thinking. I'm pulling out an old DSC PC2550 panel and my intention was to reuse the existing outdoor strobe/siren/horn but the DSC documentation says "Bell/Siren Terminals “BELL [+]” and “BELL [-]”These terminals are for powering bells or other devices requiring a steady output voltage on alarm.". The wiring diagram shows a "700mA current max" under the siren symbol.

Does that imply that the old DSC system most likely has a piezo siren (with built in driver) and not a magnet/voice coil horn?
If so should I just parallel it with the indoor piezo on the Bosch panel? The Bosch documentation says the 'relay' should be used for the indoor piezo. I could be wrong but the relay circuit doesn't seem to have any EOL fault monitoring unlike the regular siren and strobe outputs. Not a show stopper, but a bit annoying.

Looking at the Bosch documentation again there's a "(1,15) sirens running" option which I could use in place of the "(1,14) Horn speaker (OUT 1 only)" option which seems to pull the signal low without modulation. It doesn't say anything about using this for a piezo, but it seems to work with a low volume miniature piezo that I'm using for testing purposes.

[secure]

Yes DSC panels use 12v sirens.
And can put 2 sirens on the Bosch relay for int siren to do inside and outside sirens.

[alarmman]

Output 1 on the current Bosch panels is defaulted as type 1,14,0,0,0,0 for an 8 ohm horn speaker. In this mode, you will get "arm" and "disarm" chirps from the horn speaker when using Bosch remotes to arm and disarm, if siren chirps are programmed. If you change the Output 1 type to 1,15,1,0,0,0 you will get a constant voltage instead, to connect a 12V DC siren, but you will lose the ability to get siren chirps.

Having said that, there are now some all-in-one external strobe/siren combos on the market that will sense the modulated signal designed for a horn speaker, and treat it as a steady 12V input. This results in the correct sound from the siren, not a mangled, warbling sound. As a bonus, you can also get the siren chirps with this strobe/siren combo.