my wife is having surgery and i am making a alert system so she can push a button in the bedroom and it will "ring" in other rooms in the house i will have a horn in 3 rooms and the button by her bed. the problem is that when i run the 18/2 wire i am losing voltage to my horns.it sounds like a deflated bagpipe. i am running 9vdc battery i want to set up 2 9v batteries how do i need to do this and a wiring diagram would be helpful. i am sure that in series is what i need to increase the voltage or do i need a battery at each horn? they are rated 6 to 18vdc. thanks chris Wanna kill these ads? We can help!