Hello i have a 2007 ls stock radio and was replacing my front stock speakers so i put in a pair of scosche 6.5 HD 6503 250 watts 4ohms and hook them up and the work great but know my rear stock speakers are not working and i check the balance front and and rear set them to 0 and still no sound from stock back speakers ... I know the rear are 8 ohms stock and can not figure out why they don't work when they did before the front were changed ,maybe i am old school but need some input thanks ..

 

Running 4ohm and 8ohm speakers at the same time on the same amplifier won't work. You're presenting the amp with different loads. I replaced all 4 of my factory speakers with 4ohm speakers and they work fine. If you put the 8ohm speakers back in all 4 will work again. Not what you want you wanted to hear...sorry.

 

Ok will right from the factory were setup with 4 ohms front and 8 ohms in the back ,so i figure if i replaced the front with 4 ohms and leave stock 8 ohms in the rear they should all work right? well that is all i did and my my stock rears have no sound weird...

 

In my 08 panel, all of my speakers are 4ohm stock, I would even out the load all around either 8 or 4ohm all the way around and all should be good again

 

You are powering 250w rms 8ohm speakers from a stock unit? No wonder you don't hear anything.

You are sending less than 15-25w rms to 250w rms handling speakers. Shame on you.

Not to mention that you probably see half that (10w rms) since the ohm load is higher

 

. You need to read the stock rear speakers are 8 ohms that I never touch

 

Not helping a bit with your dilema, so please forgive. But rear speakers mess up your soundstage. If you are after the best sound possible then the rear door speakers are going to screw that up anyhow.

 

I had some stereo problems of my very own, that's what brought me to this site in the first place.

Yes in my '06 the front stock speakers said they were 4 ohm and the rear said they were 8 ohm. This was printed right on the back side of the magnet.

I thought this was a little odd because I have a little background in electronics, but figured who ever specked the amp in the stock radio might know what they were doing.

I replaced all 4 stock speakers in the car because they had stopped working in the HHR.

I'm incredibly cheap and really hate to buy new stuff so I tinker with stuff a lot and after applying some WD-40 to the frogs in the speakers they started working again. When I put them back in the car they would only work for a day or so then quit working again, so I removed and replaced them then built some enclosures for them and am still using them in the garage.

I have no real clue why the work fine in the garage but they do.

 

Well thanks to all reply's but i am going to buy another pair of the same brand install the same set speakers i bought for the front and put the same ones in the rear to equal out ,so 4 ohms in front 4ohms in back and see what happens

 

Hey buddy ...
I have read this entire thread and you may have received a little misinformation . There is nothing wrong with running a mixed load over 4 channels . We all do it or have done it . I am doing it now with the 200.4 Phoenix Gold amp .... Front 2 channels 4 ohm , Rear channels summed mono at 2 ohm . The 4 ohm/8 ohm will not damage your electronics .


RMS power rating/ sensitivity rating ..
The power rating of a speaker is the range of wattage the speaker will operate properly in . Nominal 125 Peak 250 .
Sensitivity rating is how loud the speaker will play at "1 watt at a distance of 1 meter " .
The higher the number the more efficient the speaker . The result of a number like 96db sensitivity rating says that speaker will be 6 decibels louder than a speaker rated at 90db . This testing is done with 1 watt . You must double your power for a 3db increase . A 6 decibel increase can be achieved by only choosing the correct speaker .

My tweeters are rated at 90db . Power range with a PMAX of 75 watts . I doubled up on the wattage for each tweeter because of the sensitivity rating . That rating told me that they would demand power to perform . So they have 142 watts per channel each . That amount of over kill is not necessary, but we have different objectives in our systems .

Hope this helped you to understand that number you put out there and some of the responses you received .
Greg