The amp in my '98 F150 was professionally installed about 6 months ago. The Kenwood HU and Infinity Reference Speakers were professionally installed a few months before the amp.
Upon installation, I got a lot of "noise" from the system. The shop owner re-adjusted the amp and was able to eliminate about 98% of the noise, just by playing with the amp settings.
The only time I hear this noise now is when I am really "pushing" the truck. Accelerating uphill while towing a trailer is the biggest offender. When I back off the throttle, the noise goes away.
I was wondering if I should install a "Noise Filter". If yes, what is the best type to install? Are there any "cons" to using "Noise Filters"?
Should I be looking for another solution? The installation looks pretty good. I do not see any obvious wiring problems.
The amp is a 4 channel Performance Teknique. Claimed output is 800 watts. It is installed under the driver's seat.
Please forgive my ignorance. This is the first time I have ever purchased a separate amp for my car. Other than the obvious improvement in sound quality, I know very little about them.

 

The biggest factors that "induce" noise into the system, is running the signal wires next to a high current cable. Are the wires run near eachother, -push em as far apart as you can further the better. Another is a poor ground, even the slightest difference in grounding impedances between the HU and amp can cause the eddy currents which basically amplify themselves. Did the installer use a star washer on the ground. If not add one!

Filters are not a way to correct a problem, they only hide it!

 

Because I am using LOCs with my factory HU unit I ended up with some noise. I have all my wires run the right way, power wire away from speaker wires and stuff. I added ground noise reducers and I now have no noise at all. With your setup, it sounds like the noise is caused by the install. I mean they did not take the care to watch out for things that can cause it. Now if they are washing there hands of it, it wouldn't hurt to try them.

 

I learned after much agrevation to put a ground loop isolator, on the rca outputs. You can get them at Radio Shack for maybe 10 or 15 bucks, worth the price.

 

Hey Dupuis, what kind of ground noise reducers are you using, i'm running with the factory 6 disc into my amp and have noise issues as well.

 

Ground loop isolaters are a last resort band-aid, at best. Most will seriously degrade your sound quality, most noticeably in the low frequencies. The are isolation transformers, which bby nature act as lo-pass crossovers. There are many other things to try first.

clean all the grounding points in the engine compartment, including the battery terminals.

Have your alternator tested for a faulty diode pack.

Make sure that your gains are set properly.

Upgrade your battery to one that has less internal resistance.

Add a stiffening capacitor to your system and enjoy the added benifits that go along with its noise filtering function. (I have even added them near the battery, as well as close to the amp, to ensure total filtering ability...)

Matt

(Not necessarily in any order, just suggestions...the stiff cap would be my first step, if wiring was verified as good...as it will bring very good 'bang for the buck' improvements...)

 

I just used ones from CC.
Mattmanyam is right, try all else 1st.
I checked everything I could without any success and just came to the conclusion that the noise is from having to use LOCs and converting an high amped signal to a low RCA signal thus not much I can do other than replace my stock hu with an after market one which I'm not willing to do. So my last thing to do was try the ground loop noise reducers and it worked. Does it affect the sound, I have no idea, but believe me, you would never know it after hearing my truck and I have had many of setup with after market HUs.

 

One more idea...

During an install that had a lot of noise, the amp case was actually grounded by a screw... That's bad in this case, we put rubber grommets between the screws and amp case, ALL NOISE WAS GONE!!

 

Good call!!! Something I never thought of.

 

THANKS!!!!