Constant Static noise when power on
 

I have read and read and searched and searched and I can't seem to find an answer to my specific problem. I have constant static noise when power is given to the speakers. It seems to be worst from the rear speakers especially my rear righthand speaker.

Speakers are:

Infinity Kappa 60.7cs front
Infinity Kappa 62.7I rear (major static)

Amp:

Infinity Ref7541a

Head:

Pioneer DEH-P310-UB

Amp power 4 awg gnd 4 awg speaker wire is all 14 awg and using two sets of 97% sheilded RCA's. Also I did a ghetto sheilding (aluminium foil taped) at all the intersections of speakerwire and the RCA's. Speaker wire is passed on seperate side of the car from RCA's, car is a 1993 Mazda Rx-7 FWIW.

Specifically all four of my speakers exhibit static noise but the rear right makes it annoying to the point where I couldn't go for a drive. Yesterday while doing a test I had only the rear right plugged in and it acted funny (tested for literally 10 seconds intermitent maybe 2 times 5s) I am wondering if that could be related in any way.

Any help or ideas would be appreciated.

Sounds like a bad amplifier. Find a different amp and try it. Disconnect all speakers and hook them up one at a time as well.

Well I don't exactly have an amplifier on hand to try out another. Is there any tests I can do on the amplifier itself?

Get an MP3 player and a RCA to 3.5mm (headphone jack) cable. plug RCA's into the amp; 3.5mm to mp3 player. This will tell you where you can start to look for your problem. Amp, or deck.

Disconnect you RCA's at your amp and use an MP3 player or discman with an 1/8" to RCA adaptor and connect to this your amp instead of your head unit. If the sound is still dirty you know it isn't being picked up from your RCA's or HU and is the amp, amp power/ground or speaker problem. But if is clean you can rule out those issues.

You can also rule out your RCA's picking up noise by using this same MP3 player method at the RCA connections at the head unit. Disconnect the RCA's and using another adaptor hook the MP3 player there, this will tell you if the noise is coming from the RCA's or originating at the HU it's self.

Next you can do as Rob said and disconnect all speakers and reconnect one at a time and check the results, it could be a shorted speaker lead feeding back through the system some how.

Also ensure all your power and ground connections are good to your amp and HU.

This should yield some answers for you.

BTW, routing your RCA's away from power sources is more an issue than speaker cables, especially amplifier power or other sources that may draw alot of current. If you have to cross paths with a power cable it is best to cross at a 90 degree angle to it. This minimizes the area of electromagnetic flux that the RCA is exposed to.

Hope this helps.

Lyle

Forgot to mention thank you for the fast reply. Just did a quick test disconnecting individual RCA's from the amp and even when an RCA is disconnected the static is still present in the concerned speaker does this mean anything?

Also I have the amplifier taken apart now so if there is anything I can look for there, I checked to see if any resistors were burned out or if any connections were desoldered and I can't see anything.

To add on to all the great things one front right speaker is now doing this constant thumping ala maximum excursion but no sound comes out any particular reason for that? Whenever it is connected it starts doing it and the Clip light flashes on my amp, is Infinity junk in AMPS?

*While typing this two responses man you guys are fast!!! You sure this is an audio forum and not a performance forum?

Also, Kyle would it be best that if they are to cross (power and RCA) that they be sheilded from eachother somehow?

Double check the ground and DISCONNECT ALL THE SPEAKERS like first mentioned. One speaker dead shorting is enough to send the whole works into protection or make the amp do odd things.

Try disconnecting the speakers like mention previously also try them on different amp channels aswell and make sure your power and ground connections are all perfect.

It is possible a single stray strand of wire could be shorted to ground or and adjacent terminal. This could cause this affect, I've seen it before. Also, if you have a small bookshelf speaker from your house or something similar that you can use to test with that will help you rule out bad speaker wiring too.

Definately related to your amp, though. I don't know much about infinity, but I would expect them to be pretty good. Not like Boss Audio or similar garbage.

Lyle

Thanks for all the pointers I will go out and buy an RCA to 3.5mm adapter in the AM and try all the steps suggested before haggeling you guys with questions.

Ohh and while removing an RCA from my amp the receptable came out stuck onto the RCA....

When you say disconnect the speakers one at a time do you mean just disconnect them from the screw in terminals or do you mean disconnect the associated RCA and the leads going into the screw in terminals as well.

FWIW about the ground the headunit is grounded reusing the OEM ground.

And out of gratuity:
http://i33.photobucket.com/albums/d52/theright7/Rx-7/Rx-7FirstDay2009002.jpg

Disconnect all the rca cables and speaker wires from the amp. Hook all the rca cables into the amp, turn the power on. Then start hooking speakers up one wire at a time and post the results.