ok so i am looking at car speakers and stereos and i am a bit confused. the speakers i want to buy have a maximum power of 800 watts. though the stereo i want has an output of 240 watts. I am wondering if the speakers of a potential 800 watts will only deliver 240 watts if connected to the stereo with the output of 240 watts. Would i need to buy an amplifier to make it possible for the 800 watt speakers to reach thier potential?

THANKS!

oh yeah i am talking about speakers that go behind the head rest of the back seats