Car Stereos: Buzzing in new f150 speakers, ground loop isolator, alpine speakers

Question
QUESTION: I have a 99 F150 and I just installed 4 new alpine speakers and 2 subs with two amps, and a new headunit.  The subs work great and so does the headunit but there is this buzzing in the speakers when i turn them on.  When the car is not running its not there but when i turn the car on it gets to buzzing.  When the rpm's go up so does the buzzing.  Is an isolator the thing i need to fix it?

ANSWER: Hi Bob.

No this happened because you ran the power wire and the RCA wires on the same side and you are getting alternator noise, try running the wires on separate sides and you will see the buzz will be gone, if you are not able to run the wires on separate sides for some reason there is something called ground loop isolator, it eliminates the annoying alternator sound, it runs anywhere 20-25 dollars and you can get it even at wal-mart.

Hope this helps.

Ed.

---------- FOLLOW-UP ----------

QUESTION: Thank you very much.  We already tried running the cables on seperate sides
and it still buzzed.  we lowered the wattage to the speakers and the buzzing
went down a little to a liveable level.   can i plug the isolator into the preamp
cables and then the other end straight into the amp? Thanks again!!

Answer
No problem man, well i dont know what kind of isolator you got, but ussually you connect the Rca's coming from the radio at the amp side, connect the Rcas from the radio on the Rca Inputs on the isolator and then it should have 2 sets of outputs choose one side and conect them straight to the amp, there is nothing really much to it. but let me know if you need any more help

Regards.

Ed