Car speakers and home stereo speakers?

Question

ok, the ohms for car speakers is apparently from 2 - 4 ohms.

for a stereo speakers it is 4 to 8.

what is the significance of that?

what would be the outcome of i were to hook car speakers to a stereo system?

what else is the effect of ohms other then resistance?

why do they have different ohms?

thank you for your time

Answer 1

If your Effective power in watts or RMS from your amplifier is rated at 100 watts per channel in to 8 ohms, then if you connect a car speaker that is rated around 4 ohms, it will be running at 200 watts in to 4 ohms. It will be louder and have more power (theoretically it will be doubled).

Car Speakers have lower ohms because traditionally, the power of car radios and amplifiers were lower than home amplifiers/receivers. Of course now, car amplifiers are much more powerful and several car speakers can handle big power amplifiers.

You need to know the power rating of your car speakers, say 100 watts in to 4 ohms. Then if you have an amplifier running at 50 watts into 8 ohms, then it can handle 100watts into 4 ohms. If your Stereo system has 100watts in to 8 ohms, it run up to 200watts in 4 ohms and it can destroy your car speakers, if you play at loud levels.

Answer 2

The ohm value represents the resistance in the coil of the speaker.  If you were to connect two 4ohm speakers in series, it would have the same resistance as a single 8ohm speaker.  If you connect two 8ohm speakers in parallel they would have the same resistance as a single 4ohm speaker.

I had a car speaker hooked up in my house to a stereo system for years. (although I did eventually blow the speaker, it used to literally shake the windows)

Series connection

  . --(+)speaker(-)-(+)speaker(-)-- .

parallel connection

    --------(+)speaker(-)--------

  . . i----(+)speaker(-)----i