Speaker Impedence

[Manolito]

Sorry for the newbie question, but I put a Sony CDX-GT210 in the wagon and my daughters cranked it up with country music and trashed a couple of the 18 year-old 4" speakers.

All I listen to is talk radio and occasional '70s music (hence the Sony CDX-GT210)

I am thinking Infinity Reference speakers, but I note that they are 2 ohm impedence. Is that OK? I thought that most speakers were 4 ohm, though I noticed that the HKs in the e36 were 3 ohm.

If I put in 2 ohm speakers, is it necessary to replace all four at once?

Thanks!

[overeasy]

i accidentally ordered 2 ohm speakers and i am returning them for this reason. 2 ohm speakers, IF compatibly with your head unit, will sound louder but with slightly less sound quality. Since I am amping all of my speakers with plenty of power, I will return the Infinities to get 4 ohm for sound quality.

The main issue for you is compatibility. Running them off the head unit won't be audiophile quality anyway so if your head unit can handle them I'd say 2 ohm might give you a slightly louder setup. I am by no means an expert, but I had the same question a couple weeks back and pple over on bimmerforums helped me out. (they have a more active car audio thread )

[Benztech]

Long story short, the lower the impedance the easier it is for an amplifier to drive the speaker. However if the impedance is too low for the amplifier it will cause it to overheat and potentially damage it. Your cd player is not capable of driving 2 ohm drivers it is the same as doubling the number of 4 ohm drivers from 4 to 8. Yes you would need to replace all four at once and you would need to use an amplifier that was at least 2 ohm stable. Simplest solution use 4 ohm drivers there are plenty of good quality 4 ohm drivers available. As for sound quality it would only be diminished if the amplifier cannot handle the increased load.