LV Battery grounding question for audio upgrade

[MrLoganRoss]

We are both saying not to connect directly to the negative battery terminal. Electrically speaking the point I show and the jump spot under the left panel are equivalent.

You will want a tight connection - I don't recall if the jump point has a nut/bolt you can connect to.

The Police Modifier Bulletin also suggests a spot that is above and to the right of the battery.

Thank you for this. I just printed it out, and it is very helpful.

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[MrLoganRoss]

Here is the interesting thing about trying to spec out the right wires and fuses. I used an amp clamp for the purposes of assessing how much power my entire system draws when playing music at the loudest I can possibly listen to it, and the result was shocking. On paper adding up my helix V8 Mark 2, my transducer amp, and my subwoofer amp: they sum to a theoretical 1700 Watts (and by way of calculation, approximately 140 Amps). By the way, that subwoofer amp is driving two JL audio 13TWV2–4 drivers.

The actual music draw, based on the amp clamp, averaged anywhere between 1 and 4 Amps - with the most challenging bass heavy tracks having short spikes into the 6/7 amp region. Huh?

Therefore I am having a hard time grappling with building out a 1/0 gauge power system, where the theoretical draw is 100+ amps, yet in reality the draw is 10 ( and that is being extremely my generous). Even if you account for inaccuracy of the amp clamp, and then double the measured draw to 20 Amps (just as a buffer and a precaution), it is striking to see what the reality is vs the theoretical.

As I decide how to finalize the wiring for the system, I would love to hear thoughts from experts about what’s going on here. Is the reality that most systems are very different than the theoretical specs of their various components, or could the amp clamp really be that inaccurate. As an FYI, I use the amp clamp on the audio system power wire (just as it’s leaving the battery in the frunk)

One last thing: assuming I go with smaller wires, even 4 gauge is more than enough to cover everything based on actual usage within the truck as measured by the amp clamp. And on top of that, properly fusing that four gauge wire reduces any risk to it right?

 

[MrLoganRoss]

One last question: I’m assuming that various ground points wouldn’t cause a drastic difference in amp reading from the amp clamp, correct?

 

[K6CCC]

The actual music draw, based on the amp clamp, averaged anywhere between 1 and 4 Amps - with the most challenging bass heavy tracks having short spikes into the 6/7 amp region. Huh?

High probability that your clamp on amp meter can't respond to peaks. so it is reading a somewhat fast average rather than actual peaks.

 

[MrLoganRoss]

Hi. It shows the peaks. You can also set it to show max instead of instant

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