I stumbled upon this the other day:
https://electronics.howstuffworks.com/surround-sound7.htm
Seeing how easily you can create a matrix surround system using a two-channel home amplifier makes me interested in applying this in a vehicle.
My only concern about this kind of setup is what kind of impedance a two-channel car amp would see when using 4-ohm speakers (since most car speakers are rated at this)? I only know the basics of Ohm's law, so I'm somewhat stumped... Assuming it doesn't create too low of a resistance rating for any affordable stereo amp to handle, I'd like to give surround sound in the car a try.
I figure that this kind of setup would create a much more realistic sound stage, as compared using the common methods of adjusting for rear fill.
This setup will give you 4 ohms resistance using 4 ohm speaker. The method in the link combines parallel and serial wiring to keep the resistance the same. HOWEVER the kick back is that the power will be spread out across all 4 speakers and you'll lose directional sound. So your 200 watt RMS amp will output only 50 watts RMS to each speaker.
It won't be realistic in terms of following the soundstage and imaging, but it will fill in your car with music more evenly throughout the cab. That's just a matter of testing and tweaking the system.
Good Luck!
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