i have two 4.5" audiobahns on my dash two 6.5" in the front two doors and two more in the back doors and i wanted to put two more 6.5" speakers in the back underneath the rearwinshild will i burn out my head unit if i dont use an amp
Yes, to many speakers can fry your head unit. Most head units have a limited load of 4 ohms per channel. That means 1 speaker per channel. If you want to run multiple speakers you will need an amp. Look for an amp that is 2 ohm stable if you want to run 2 speakers per channel. I have 2, 2 channel amps that are each 2 ohm stable to power 8 speakers.