Ignition/Alternator Noise

[woyster_00z71]

I recently installed an amp in my 01 Tahoe to run a subwoofer and I am getting quite a bit of alternator whine. What are some tips to eliminate the whining without adding a noise filter?

 

Thanks,

B.J.

[tmf6902]

try a different grounding point. And make sure your amp isn't grounded on something painted.

[J-rod]

Ditto on what tmf said ... I just installed a buncha stuff in mine around Thanksgiving and had the same problem. I tried stuff, researched, called Crutchfield (where I ordered several of the components), and tried more stuff. Anyway, from my many hours of reading, it seems that the most common problem is grounding. So yeah, make sure the ground wire is at least the same gauge as your +12 and it should be as short as possible and no longer than 18".

 

Is this sound coming through the subs or through some hi/mid ranges that are also amplified??? I ask b/c the crossover on the subs' signal *should* filter out alternator whine (if that's what you're hearing) since the frequency of the whine is 3 times the engine's current RPM which is well beyond the frequencies the subs should be reproducing ... even at idle. Of course, that's if the whine is being introduced at the inputs and not from the chassis ground. (Test this by unplugging the inputs from the amp ... if ya still hear it, check the ground, else it's coming in before the signal gets to the amp.)

 

On a related note, mine turned out to be the stinkin patch cables. I bought some new (and actually cheaper) cables, routed em the exact same way and no more whine (which was being reproduced by the door speakers in my case). Seems my cables were made just right so that they acted like friggin antenas in my truck, picking up the alternator whine.