If i am adding speakers to the stock system do i need an amp

[jeffgtx]

i know very little about stereo physics, but i am guessing if i want to take a 4 speaker systema and make it 8, i need more power somewhere, right?please give a rookie a lesson in amps.

[Jahntassa]

Basically. Yes. Though how do you want to make it 8?What kind of speakers do you want to install, how?

[ZubenElGenubi]

Even if you decided just to replace the existing speakers, you might need more power because the stock speakers are 2 ohm and most aftermarket speakers are 4 ohm. Translation: loss of volume.

[jeffgtx]

i dont have moon/tunes.can a do it yourselfer add an amp pretty easily? i imagine i need to buy some sort of connector for the rear of the stereo and run it to the amp, and will that fit under the pasenger seat like moon n tunes?

[JohnC]

Kind of a side note here...We drive a Saturn stationwagon for the Humane Society , it has speakers mounted in the tailgate facing forward and the sound is much better/clearer than the rear passenger door location of the Vibe's.I wonder if there has been a speaker install on a Vibe back in the tailgate? I have the rear seats folded down in the Vibe all the time so that is not a problem blocking the sound.

[GMJAP]

I imagine what you would need is a speaker-level-to-line-level converter to run off the existing channels, drive an amp with it, and run the amp to the speaker.Question would be - Do you amp all speakers, or just the additionals? The former would be more work and $, but may give a more uniform sounding system.

[Jahntassa]

Judging from what he told me in IM, and not knowing the specs of the speakers he wants to use, a small 2 channel amp should be fine.. Though, it depends on the speakers.It's a matter of sound staging re: the rear speakers. First of all, the stock speakers are midrange only..you really need some better speakers in the rear door to do better. Of course, tweeters in the top of the door, like M&T in the front, would really help.

[IDT_Designer]

Because you are adding an additional 4 to the 4 stock speakers, you could simply not buy an amp, and replace the eight speakers with 8 ohm speakers. that would result in 4 channels with 1 set per channel at 4 ohms, no strain on the factory system. you wouldnt have additional faders anyway, so setting up channels in parrallel with 8 ohm speakers (partsexpress.com) will give you more speakers same power no addtional amps

[Jahntassa]

And finding replacement 6.5" and new 3" speakers at 8 Ohms that sound decent and AREN'T designed for home use is not an easy task. But yes, that's one way to do it.

[jeffgtx]

thank you everyone for the tips. i think i have the components lined up and will post the result when i get it done.thanks.