Aux battery for audio

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1lejohn

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I don't know because I'm not one to crank the system with the truck not running. It sounds better at 14.2 volts than at 12 anyway.
Understood just playing devil's advocate.
 

Grit dog

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yes and no. My alt is a factory unit pushing 94 amps. However, at 1100 WRMS, that's 76.4 amps just for the amplifiers. But yes, I may want to run the audio without the engine running and still be able to start my truck when ready. and Yes, it is a traditional camper load but not lights and fans....thumping music.
You’re still tracking right. And you provided enough info originally that should have quoted down the “whys” even though you were only asking about the “how’s”. It happens, it’s the internet.
One guy running a 1900W stereo off of a crusty old Diehard battery and a kick @ss alternator is not the only way to properly accomplish the desired results.
Keep on keepin on.
I’m sure your installer or the voice in the back of your head will tell you to make sure the wiring is large enough to handle the load efficiently. That was my only comment after you sorted out the battery isolator thing.
Cheers!
 

SquareRoot

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You’re still tracking right. And you provided enough info originally that should have quoted down the “whys” even though you were only asking about the “how’s”. It happens, it’s the internet.
One guy running a 1900W stereo off of a crusty old Diehard battery and a kick @ss alternator is not the only way to properly accomplish the desired results.
Keep on keepin on.
I’m sure your installer or the voice in the back of your head will tell you to make sure the wiring is large enough to handle the load efficiently. That was my only comment after you sorted out the battery isolator thing.
Cheers!
:oops:...:popcorn:.....PS. Diehards suck. I'm no longer going to ask why. I'm gonna sit down here in the bottom of the rabbit hole and wait for company.
 

1987R30

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You’re still tracking right. And you provided enough info originally that should have quoted down the “whys” even though you were only asking about the “how’s”. It happens, it’s the internet.
One guy running a 1900W stereo off of a crusty old Diehard battery and a kick @ss alternator is not the only way to properly accomplish the desired results.
Keep on keepin on.
I’m sure your installer or the voice in the back of your head will tell you to make sure the wiring is large enough to handle the load efficiently. That was my only comment after you sorted out the battery isolator thing.
Cheers!
The factory connections to the aux battery are for charging. They don’t carry the load for the audio system
 
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CalSgt

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My original post wasn't clear. I've already decided to add the aux battery. I was asking where I would physically connect the amplifiers to the aux battery. I guess I go through the firewall and connect directly to the Aux Battery terminals.
Basically….
Positive amplifier wire directly to the battery terminal fused within 18” or so of the battery

Most people ground to the body near the amplifier, I took it one step further and grounded to the frame under the cab. That’s one of the reasons everyone is stressing the importance of the ground at the battery, the wiring needs to be able to support the current.

I suppose there is no reason you can’t wire the amplifier ground directly to the auxiliary battery. Quality copper amplifier power/ground wire is expensive so it is a cost saving to let the chassis carry the ground for most of the way, also it’s one less bulky wire to route to the battery.

ETA: you can go through the fire wall, or route along the frame and through the floor board under the seat or any way you can get the wire where it needs to go without putting it in harms way
 
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Scribbles

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I have a 1987 R30 w/454 and TH400. It has the camper special option including a tray for an auxiliary battery. It has the upgraded 94 amp alternator option. I am installing 1100 Watts of audio equipment. I was thinking of installing the auxiliary battery and running the amplifiers off that. But where do I connect to the aux battery? I assume the alternator charges the aux battery?
Hello, lots of good info here. Mainly the one about using the correct relay. The one from Rockauto that you ordered doesn't have enough capability to carry the current. This is the correct relay. http://www.metraonline.com/part/IB500 . I only run one in my show truck because I play it all day at shows, My batteries in my 90 Burban are in parallel but I don't have anything running other than a base radio with a 10in sub on a JL 1000/1right now. hope this long ass message helps but If you need any help feel free to email me at [email protected] I'm a Mastertech installer with over 30yrs exp.
 

1987R30

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Hello, lots of good info here. Mainly the one about using the correct relay. The one from Rockauto that you ordered doesn't have enough capability to carry the current. This is the correct relay. http://www.metraonline.com/part/IB500 . I only run one in my show truck because I play it all day at shows, My batteries in my 90 Burban are in parallel but I don't have anything running other than a base radio with a 10in sub on a JL 1000/1right now. hope this long ass message helps but If you need any help feel free to email me at [email protected] I'm a Mastertech installer with over 30yrs exp.
Hmmm…i didnt even think to look at the rating for the rock auto relay. I was thinking it was such a specific item how could they get it wrong. But youre right. Only rated for 30 amps. My alternator can put out 94 amps. Thanks for the heads up. I will switch it out. As for my original post, i was wondering where the amplifiers would get their power. I now believe the wires will go through the firewall and connect straight to the aux battery. Yes? No?
 

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