Another Whiner

[speedracerx 10+ year member]

I just hooked up some more of my components to make sure they work before final install. I wired in my two mid woofer amps, 2 caps, and my Audio Control X-over. Everything was checking out tell I kicked on the battery charger, it introduced a hum that wasn't there when charging before additional components. I have the battery mounted in the trunk so it was easy to ground and power everything directly to the unused side terminals on my Optima. I changed up the distribution blocks and cap wiring-no help. I up sized the ground wire running up to the head unit, no help. I unhooked the caps (sparkity spark) No help. Finally I unhooked the x-over and reset the various filters in the head unit and amps, the hum was gone (cant properly split amps to 4 way without the x-over though). I purchased the crossover used, but I cant imagine it would only add noise when charging battery or running engine (running also adds additional engine noises) if it is damaged. I started wiring up a dedicated head unit power wire and relay for new dedicated ignition lead from battery but I don't think thats gonna do it. I didn't think to unhook the top post battery cables (to everything but audio) and replace charger, but the only metal to metal contact in the whole system is the head unit case to the dash. Should I give up on the crossover or am I missing something else to check?

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[Prowler573 5,000+ posts]

The bit that I'm having a hard time with is three (3) five farad caps.

Why? Just, why?

At any rate...it's likely the battery charger introducing your 'hum.'

Chargers are generally meant for nothing more than what they were built for - to charge batteries....not provide a power source for car audio. The power supplies in most chargers feed "dirty" power and that hum is more often than not unavoidable.

 

[Worlddre 5,000+ posts]

could be with that 4way crossover that you have a good number of rcas back there maybe one or two were siting next to a power wire in a unflattering manner introducing your hum

 

[disturbedfuel15 10+ year member]

rcas back there maybe one or two were siting next to a power wire in a unflattering manner introducing your hum

I was told power wire and RCAs cause no interaction between eachother, so this cannot be the source of his "hum," or "whining." If this is not what you were referring to, I apologize.

 

[speedracerx 10+ year member]

I'm only using 2 of the 3 caps. Finished product will have trick easily removable sub amp rack and removable heavy *** sub enclosure, leaving front stage amp rack with 1 cap installed (just reset low pass on front woofers) so I can jam while I'm smoking the stripped down trailer queens at the drag strip. I've laced the harness nicely- nothing touching or tied down yet. Interior currently stripped for Fatman insulation and fiberglass projects. Whatever it is, it's the x-over thats has an issue with it. I have another Kenwood head unit I can quickly patch in in the trunk to see if that changes anything.

 

[Worlddre 5,000+ posts]

I was told power wire and RCAs cause no interaction between eachother, so this cannot be the source of his "hum," or "whining." If this is not what you were referring to, I apologize.

in some cases this is true in others its not...power wire being close to an rca can create induced noise doesnt always happen but it is very possible.

 

[disturbedfuel15 10+ year member]

in some cases this is true in others its not...power wire being close to an rca can create induced noise doesnt always happen but it is very possible.

Elaborate... I'm about to start a poll on this **** topic, because I keep getting so many mixed answers. Some say no, some say yes, some say maybe... //content.invisioncic.com/y282845/emoticons/uhoh.gif.c07307dd22ee7e63e22fc8e9c614d1fd.gif I'm so confused. All I know is that I got *****ed at when I said what you said about the RCAs / power causing a "whining" sound.

 

[Worlddre 5,000+ posts]

from my own personal readings ive found that power wires carrying DC are surround by a small magnetic field. This magnetive field can be (but is not always) induced into the rca or signal cable and cause a noise problem.... tis commonly referred to as inductive coupling

 

[disturbedfuel15 10+ year member]

^^^

Try telling that to helotaxi

read: http://www.caraudio.com/forum/showthread.php?t=188002

 

[lincolnls 10+ year member]

if you are using shielded twisted rca's you should be able to wrap your rca's around your power wire and have no issues wahts so ever

 

[johnecon2001 5,000+ posts]

If you have a properly grounded system... both of those arguments are moot.

 

[Lil Poot 5,000+ posts]

you run brahma's with a boss amp?

 

[speedracerx 10+ year member]

you run brahma's with a boss amp?

Been waiting for someone to ask about that, kinda like ketchup on a steak,huh? I upgrade when the price is right, but the boss can go .5ohm and truly does hit hard. I'll pay the bucks for quality amps that are going to play frequencies where you can actually hear distortion. A lot of headroom helps keep an average amp in its sweet spot too. I'm more content with my Boss than my Focals, and you are probably thinking the same thing I would if someone told me that.