Standard speaker system impedance?

[525iZA]

I think my car has a standard 6x speaker system. 4 in front and 2 in the rear.

What is the impedance of these speakers? A friend of mine reckons that they may not be compatible with a new head unit. I.e. they will only utilize half of the output from the head unit, or some such theory.

Help! I'm clueless with these things.

[whiskychaser]

I think my car has a standard 6x speaker system. 4 in front and 2 in the rear.

What is the impedance of these speakers? A friend of mine reckons that they may not be compatible with a new head unit. I.e. they will only utilize half of the output from the head unit, or some such theory.

Help! I'm clueless with these things.
I think your friend is right - if you dont have the right load (impedance)across the amp it will blow. Sorry I cant help with the numbers but somebody is bound to jump in on this

[Ross]

4 ohms. There is a factory amplifier in the rear, the speakers are driven from the amp not the head unit.
Most modern head units will overdrive the factory amps input.

[pingu]

+1.

Bu on the other hand, most indoor hi-fi speakers (at least here in Europe) are 8 ohms (instead of 4 ohms like a car). This is because in a car, there is only a relatively low voltage (+12V) available so it makes more sense to have a lower impedance for the speakers.