Aux battery for audio

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1987R30

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Grit dog said:
^Has to be as big as the + wire.
Or no worky and you fry stuff.
10ga off of any automotive size battery is merely an accessory load.
10ga for a ground is just silly.
Click to expand...
It's the factory ground. I don't work around wire enough to be able to tell the size by looking at it. It may be #8. Regardless, it is an accessory load. I plan to only run my new audio system (Radio and two amplifiers) off the aux battery.

I got my replacement relay from Rockauto. It is a hefty part. However, I couldnt install it due to coming down with a head cold. Also,, We're dealing with some weather issues here in Florida.
 
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2 AWG welding cable works very well.
 
SquareRoot

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Grit dog said:
Just pick what kind of isolator combiner you like.
Click to expand...
:confused:
  • Almost exactly.
  • Awfully good.
  • Deafening silence.
  • Freezer Burn.
  • Living dead.
  • Loyal opposition.
  • Old news.
  • Only choice.
 
Grit dog

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1987R30 said:
It's the factory ground. I don't work around wire enough to be able to tell the size by looking at it. It may be #8. Regardless, it is an accessory load. I plan to only run my new audio system (Radio and two amplifiers) off the aux battery.

I got my replacement relay from Rockauto. It is a hefty part. However, I couldnt install it due to coming down with a head cold. Also,, We're dealing with some weather issues here in Florida.
Click to expand...
Ok, fair enough. Suffice it to say an 8ga ground for a battery that size running 2 amplifiers is way undersized.
But seems like the experts here who haven’t provided any meaningful input think the good advice you’re getting is dumb. So maybe they could help you….
 
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What are you trying to accomplish by installing a second battery? IF it's just for the purpose of running two amps, why do you think you need two batteries? I'm just probing you on your knowledge of audio equipment. I have put together probably over 200 systems over the years and I know a bit about them. Not everything, but enough. Can you post what amps you are using?
 

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Grit dog

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SquareRoot said:
What are you trying to accomplish by installing a second battery? IF it's just for the purpose of running two amps, why do you think you need two batteries? I'm just probing you on your knowledge of audio equipment. I have put together probably over 200 systems over the years and I know a bit about them. Not everything, but enough. Can you post what amps you are using?
Click to expand...
First post. 1100W (yes not specific peak or rms and @ what impedance….probably another funny word to @Rusty Nail.)
Also first post, he has a truck that came with a dual battery setup it appears.
But correct, hasn’t answered “why” 2 batteries are needed. We need to get past 8ga battery grounds first. However it’s reasonable that 1100W of amplifier can or will draw more power than a 94 amp alternator is putting out on average. Hence a great reason for some additional reserve capacity.
 
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That's what happens when one jumps to the latest post. A good battery and alternator will suffice for 99% of any system one could put in a Squarebody unless your a nutcake and have blow thru subs in the bed. Now if the second battery was intended for other accessories that might be used in a camper type scenario, I could understand the hassle and expense of a dual battery setup.

I'm pushing 1900 RMS watts like it doesn't know it's there. PowerMaster 150 amp alt, 4 gauge charging wire (welding cable) and 1 gauge feed cable to the amps. It might sound like overkill but it's a once and done with room for increased capacity (wicked me has some idears). To each their own but be aware of those Rabbit Holes.
 

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SquareRoot said:
That's what happens when one jumps to the latest post. A good battery and alternator will suffice for 99% of any system one could put in a Squarebody unless your a nutcake and have blow thru subs in the bed. Now if the second battery was intended for other accessories that might be used in a camper type scenario, I could understand the hassle and expense of a dual battery setup.

I'm pushing 1900 RMS watts like it doesn't know it's there. PowerMaster 150 amp alt, 4 gauge charging wire (welding cable) and 1 gauge feed cable to the amps. It might sound like overkill but it's a once and done with room for increased capacity (wicked me has some idears). To each their own but be aware of those Rabbit Holes.
Click to expand...

My impression was that he wants to run dual batteries not because the main battery/alternator is inadequate, but rather for the ability to run the audio for extended time periods without leaving the truck running or risking depleting the main battery to where engine start fails. I can see the appeal to that if you are often in a position where you want the music to be playing but don't want to be running the engine constantly...in that regard to becomes more like a traditional camper load but instead of lights and fans, its music.
 
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Grit dog said:
First post. 1100W (yes not specific peak or rms and @ what impedance….probably another funny word to @Rusty Nail.)
Click to expand...

1100 WRMS.

The DVC subs will be wired in parallel for a combined resistance of 1 ohm. Still working on how I want to set up the other speakers. The subs are on their own amplifier.

Grit dog said:
Also first post, he has a truck that came with a dual battery setup it appears.
But correct, hasn’t answered “why” 2 batteries are needed. We need to get past 8ga battery grounds first. However it’s reasonable that 1100W of amplifier can or will draw more power than a 94 amp alternator is putting out on average. Hence a great reason for some additional reserve capacity.
Click to expand...

1100/14.4 = 76.4 amps (just for the amplifiers)

My charging system is rock solid.
I don't want to swap the alternator to 140 Amp and put everything on a single battery
It's easier and more cost efficient to add the aux battery ($100) then to install a 140 amp alternator ($250)

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.
 
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SquareRoot said:
That's what happens when one jumps to the latest post. A good battery and alternator will suffice for 99% of any system one could put in a Squarebody unless your a nutcake and have blow thru subs in the bed. Now if the second battery was intended for other accessories that might be used in a camper type scenario, I could understand the hassle and expense of a dual battery setup.

I'm pushing 1900 RMS watts like it doesn't know it's there. PowerMaster 150 amp alt, 4 gauge charging wire (welding cable) and 1 gauge feed cable to the amps. It might sound like overkill but it's a once and done with room for increased capacity (wicked me has some idears). To each their own but be aware of those Rabbit Holes.
Click to expand...
Thats a good electrical system you have there, but how does it do if the truck isn't running? How long will your only battery last , and still start the truck? Just saying.
 
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1987R30

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SquareRoot said:
That's what happens when one jumps to the latest post. A good battery and alternator will suffice for 99% of any system one could put in a Squarebody unless your a nutcake and have blow thru subs in the bed. Now if the second battery was intended for other accessories that might be used in a camper type scenario, I could understand the hassle and expense of a dual battery setup.

I'm pushing 1900 RMS watts like it doesn't know it's there. PowerMaster 150 amp alt, 4 gauge charging wire (welding cable) and 1 gauge feed cable to the amps. It might sound like overkill but it's a once and done with room for increased capacity (wicked me has some idears). To each their own but be aware of those Rabbit Holes.
Click to expand...
My installer had the same recommendation: update the alternator for most non-competition applications is all I needed. However, my existing alternator is strong, and it's cheaper to install the aux battery then to replace the alternator. And I can run the audio without running the engine.
 
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1987R30

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YakkoWarner said:
My impression was that he wants to run dual batteries not because the main battery/alternator is inadequate, but rather for the ability to run the audio for extended time periods without leaving the truck running or risking depleting the main battery to where engine start fails. I can see the appeal to that if you are often in a position where you want the music to be playing but don't want to be running the engine constantly...in that regard to becomes more like a traditional camper load but instead of lights and fans, its music.
Click to expand...
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.
 
SquareRoot

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1lejohn said:
Thats a good electrical system you have there, but how does it do if the truck isn't running? How long will your only battery last , and still start the truck? Just saying.
Click to expand...
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.
 
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1987R30

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1lejohn said:
Thats a good electrical system you have there, but how does it do if the truck isn't running? How long will your only battery last , and still start the truck? Just saying.
Click to expand...
This is the purpose of the aux in a camper setup. I'm simply not doing a camper. I'm doing music. This is a problem not addressed with a single battery.
 
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