I know that an EST Genesis speaker strobe will at least have the strobe flash when powered with out a voice module, but what about sound? If only power is applied to the Genesis speaker, does it make a sound?
No, you need an amplifier or some kind of device that puts out sound into it.
In order to put sound into the speaker you need a 25V or 70V (25 preferably) PA amplifier in order to boost the signal enough. Speaker/strobes contain a transformer on the back which is designed to step down the signal from a PA amplifier to something the voice coil in the speaker can use without blowing up. The reason why the voltage is stepped up so high by the amplifier is so that the audio signal can travel very far.
If you have a powerful enough amplifier for a stereo system that still would not work. If you somehow got ahold of an audio transformer and wired it properly you would actually be able to change the voltage so that you can drive the speaker on the speaker/strobe.
If you power the speaker directly from 24 volts you will hear a quiet buzzing sound. Leaving it on too long may break the speaker’s voice coil, so do not do that.
Of topic: so there are 4 terminals. 2 for strobe(24v?) 2 for speaker(25v or 70v?) Correct?
Technically this is on topic…
You are correct, 4 terminals, 2 for strobe, 2 for speaker.
Thanks. Could you explain watts?
In terms of fire alarm speakers, they’re tapped at a certain wattage to regulate the loudness of the sound coming out of them.
Much like modern strobes have different candela settings to change the brightness/intensity, fire alarm speakers have different watt settings to control how loud they are. A speaker tapped at 1/2watt might produce 80db at 10 feet, whereas if you change it to 1watt, it might produce 86db at 10 feet, this of course all depends on the speaker and you can find all of this information on the cut sheet. It makes calculating your amplifier loads extremely easy, as they’re also rated in watts. A fire alarm system might have a 50 watt amplifier, so you can stick 50 speakers tapped at 1 watt on there. Or 100 speakers at 1/2watt. Or 200 speakers at 1/4watt, or 400 at 1/8 watt… of course in a real world application, you’ll leave some type of spare capacity, but you get the idea. Most FA speakers are tapped at 1/8watt or 1/4watt probably.
In terms of the math, ohms law is v=ir (voltage=currentresistance), well for watts you have p=iv or power (watts) = currentvoltage, but none of this is needed to figure out your loading on your amplifiers.
Thanks !
Thank you very much!