Federal 950i

I recently acquired a Federal 950i, and I was wondering if there was some way I could hook it up to my stereo? Thanks!

Your stereo is designed to power a low impedance load. To operate a fire alarm or PA speaker you would have to bypass the transformer and connect directly to the 8 ohm speaker.

The other way is to use another matching transformer in reverse. Connect the speaker side of the transformer to the stereo and then use the 25 volt side to feed the transformer of the FA or PA speaker. This is inefficient but it works. I have used this method to connect a “boom box” to a 25 volt riser feeding amplifiers in transponders to provide a music signal for speaker inspections when the customer will not allow the alarm tones to be used. Later on I wrote a custom audio message in those panels to make inspections easier.

I would imagine the tonal sound quality would not sound great by todays music and Bluetooth speaker standards due to the narrow freq response range for that fire evac speakers are designed for. Although, the newer Boise supervised units sound pretty good.

Nice idea on the music feed during inspections as opposed to alarm/evac tones.

Another trick I use during day time, occupied, inspections in our larger buildings. Is to use a 2 watt GMRS radio with Vox, put the panel in audible walk test with the local panel speaker on in low volume mode, place the radio in Vox mode next to the speaker, and then manually disable the speaker/strobe and other outputs. I then carry a second radio on that frequency, and start testing at the closest device, the smoke above or pull station, and you then hear the panel call out via radio “Testing, Channel 1, Device 113” etc.

This works well for the older and newer Simplex 4100 series, as well as the Siemens MXL, and XLS’s. Although, I initially started doing this with the 2001 panel using an Alarm Controls UT-1 Timer and Sonalert wired into a separate 2001 CPU card that I carry with me for inspections. You start the inspection by tripping the first and last alarms with the existing CPU card, then power down and swap CPU cards. Now, when the new alarm comes in on the test CPU card, the sonalert momentarily sounds tripping the Vox radio, and trips the Alarm Controls UT-1 relay which is programmed for delay trigger on mode of about 2 to 4 seconds, it then triggers it’s relay wired through the CPU’s reset button, and the panel has now sounded an alarm via radio and then resets itself awaiting the next alarm i.e, pull, heat, smoke, water flow etc.

As a one man silent/audible radio walk test during the day, this works very well. I then schedule the building for a 6am full A/V test in battery mode, with shutdowns, doors, smoke evac, elevator recall etc.


I agree on the above with the sound quality issues. Human hearing has the frequency range of something like 200hz to 20khz (give or take, this is off the top of my head). Human vocal range however only has the frequency of like 500hz to 3khz, so most fire alarm speakers are only designed for that limited range. POTS is too I think, so if you’ve ever heard music over a land line telephone and it sounded like crap, that’s why. To get the full 20khz range you need an actual music speaker designed for it.

Even the new “high fidelity” fire alarm speakers designed to meet the newest intelligibility requirements have a limited frequency range of like 300 to 8khz.