I recently took on a new job at a school district. On the intercom systems where Valcom is installed, the original installers installed paging in the hallways of the schools using amplifiers wired for 25 volts. Why would anyone do this. I was thinking 7o volts was the normal. The paging sounds muffled at all locations. Also, they used the Aux input of the amp, instead of the telephone input for the Valcom system.

At 1 particular location, they installed a paging amp for one Zone, and self amplified speakers for another zone. I get a call today, and they reported that the zone the amp is on is bleeding onto the zone the self amplified speakers are on, causing the self amplified speakers to be broadcasting outside the school when the page was meant for inside.
When I looked at this I figured you shouldn't mix
self amplified speakers with speakers driven by an amplifier, or this could cause bleed over.

Am I correct, or am I missing something? Also, could the fact that all inside paging only speakers being on a 25 volt system and the amp connect to the aux port cause the muffle sound?


Gerald Ducote
NWA Telcom
[email protected]