I just went to Best Buy today and bought two Infinity 5x7's for the doors. They sounded awesome at first. Loud and crisp with plenty of bass. Then i turned it up pretty loud and the speakers cut out. so i turned it down and they came back on. The guy at Best Buy said the speakers need more power than the stock amps from the Mach system can give and i need a more powerful 4 channel Amp to support the 4 speakers. I'm going to get the same two speakers in a month or so for the back so what kind of AMP do you guys suggest that isn't too expensive and will put out plenty of power. The speakers are a pair of Infinity 6822cf 5x7's with a max power of 180 watts. (and it says something about 2.65 ohms)

As you can see i don't know a damn thing about car audio. LoL! Any help would be greatly appreciated.

 

How does this AMP look? and is there a reason it is so cheap?

http://cgi.ebay.com/JENSEN-840w-4-CH...ayphotohosting

 

I'm sorry to say, but you made a big mistake shopping at Best Buy. Most people on here, or any audio forum, would suggest Best Buy only to hear the product, then going online and buying it.
As far as not having enough power, I think that's wrong. Infact, know. My premium system in my '98 Mustang has 130-Watts going to each speaker. So, I'm assuming the Mach would have more power.

But here's where you went wrong with the actual purchase. For real quality sound, you should've gotten a Component System [Which consists of a mid-range woofer and a tweeter with a CrossOver] and most of them are 4-ohms per side which makes the choice of amps really easy. If you get the ohms wrong, you basically either rob the speaker of power or damage the speaker [if not fast, very slowly] by giving it too much power.

As for those ohms, you have to try to find an amp that has 60-80wattsRMSx4 @ 2-ohms.
If you give those speakers their max power continiously, they'll blow before you have time to jam out.


As for getting another pair for your rear, don't bother. You should get a component set if you want really good sound. But that's just my biased opinion.


EDIT:: I'm pretty sure my stock amp is 100x4, but I'm not completely sure. So, if you consider the Premium version is < than the Mach system, then it'd lead one to assume that your stock amp is either too powerful, or perfect for those speakers. But it might be 4-ohms.

 

do not listen to ANYTHING they tell you that is install related, and you can throw away %50 of the sales related stuff as well.

Did you or do you have a mach system in the car?

 

yea it has the Mach 460 system

 

The impedance is your problem.
At 2.65 Ohms, those speakers present a very small load for the amplifier, allowing too much current to be drawn from it. The amplifier is just shutting down as a safety.

You have two options. Upgrade to an amplifier that has stable output at 2 Ohms, or solder a 1.5 Ohm resistance inline with the speakers to raise the impedance up to 4 Ohms. The downside is that you'll be wasting amplifier power whis way, but it's a cheap alternative to use while you upgrade the system.

 

How does this one look? It's pretty cheap and I know DUAL isn't a bad company. I hope I get some good feedback for it cause I saved it to my favorites and I could finally stop searching like crazy for something cheap, but good quality. Remember i'm just trying to power the speakers, nothing big like a woofer.

http://cgi.ebay.com/DUAL-XPA4100-4CH...ayphotohosting

 

You always have to look at these specs:
(Pulled from the amp's spec sheet)
Total harmonic distortion: 1%
Signal-to-noise ratio: 72 dB

The low S/N ratio means that this amp will not produce clean sound.

If you want to stay within a $75 ~ $120 budget; JBL amps are a good value for that range.
I can recomend this one:

JBL CS60.4
http://cgi.ebay.com/JBL-CS60-4-CAR-4...QQcmdZViewItem

Mind you, It's not the best amp in the world, but at the price range you want to be in, its about the best you can get. And it seems to be a perfect match for your speakers as far as power / impedance goes.

 

Ya know what, you definately sound like you know what you're talking about Spyder, and I'm gonna take ur word for it. I just went to that site and bought the JBL Amp you suggested. Not only does it meet the requirements and stay in my price range like you said, it looks pretty sweet too. LoL.Thanks for all your help man and i'll be sure to post on here when I get it and install it. One quick question though... Is there anything else i'm gonna need to buy to do the install?

 

No problem[8D].
We're all here to help.

What else will you need?

Definitely an amp wiring kit.

If the Mach system (Not familiar with it, sorry) has RCA outputs, you can just conect it straight to the amp. If not, try to find a compatible harness that will give you RCA outputs allowing you to bypass the amp, or worst case scenario, splice your own cables.

If you don't feel comfortable doing it yourself, just take it to a reputable local shop