I need a lesson in radio 101
Lesson 1: Radio is the one part of electronics where you can make current flow in an open circuit!
Originally Posted by James1549
The rear speakers have 4 wires to them. Are they powered, or passive?
4 channels go to the 2 subwoofers in the rear. They are double coil woofers.
So they ARE passive. I was sure (but never cared enough to check) that they were supplying power to small amps in the speakers themselves. (I've seen that done in the 70's and 80's in Land Mobile Radio to allow an auxiliary speaker to run at somewhat higher power output than the original design called for.)
But
double coils? In 30 years of working audio PAs of up to 1,000 watts, I have never seen this before. (My only experience with
high power audio is in outdoor weather warning sirens.)
What is the idea of running two coils? What are they trying to accomplish and just how common is this?