wiring two amps

I am hooking up two amplifiers to my cousin's 1996 BMW M3.

MTX Thunder 564 for the components and a Kicker KX1200.1 for the sub.

The battery is in the trunk, and to be honest I have never done an install in any vehicle with the battery there. And so the questions I have regard the installation of the power and ground wires.

Can I run a short 0 gauge wire from the amp to a powered distribution block for the amps? Will this also count as the inline fuse that is normally positioned under the hood on most cars? And as far as the fuse sizes go, what sizes do I use? Because the two amps have differing amperage ratings. Would circuit breakers, or two separate wires from the battery be better?

Also, can I run another 0 gauge wire from the negative post on the battery to a ground distribution block for the amps?

I would appreciate any help.

Thanks

Zero gauge would be overkill for your application. Fuse whatever power wire you have as close as you can to the battery and then fuse again when you distribute and downsize. Ground on the body as close to the amp as possible.

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Okay. But the space between the power connections of my amp and the battery is only like two feet. So am i supposed to try and fit the fuse holder and distribution block in that short of space? And as far as the ground goes, isn't one of the best grounding points in a car at the negative terminal at the battery? I'm just trying to clarify.

pv13]O wrote:

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ay. But the space between the power connections of my amp and the battery is only like two feet. So am i supposed to try and fit the fuse holder and distribution block in that short of space? And as far as the ground goes, isn't one of the best grounding points in a car at the negative terminal at the battery? I'm just trying to clarify.

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Yes, you must "fit" your fuse and power cable and distro block if you use one.  Wire is flexible, you can make it fit... as far as grounding, the battery negative terminal is not the best place to ground.  Actual system ground is the case of the vehicle's alternator and the battery uses the vehicle chassis to connect there, so if you wire to the battery negative you will simply be adding the load of your amps to the negaitve battery cable.  If you follow the negative battery cable, where is it attached?  My bet is to the vehicle's chassis.  You want the amp grounds to be short runs to the chassis and bolted on to a point you have scraped free of all paint.  You may want to read the grounding threads in the Car Audio Hot Topics forum.

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Okay thanks. I will ground the amp at the chassis ground. And I understand that the power wire going to the battery has to be fused, but do I need to have both a fuse holder and a distribution block? Can I just have a distribution block? Also is the 0 gauge really an overkill? Thanks

You can use the zero if you insist, but yes it is overkill, and yes you must fuse, two feet between battery and ampifier?, my guess is the battery is in the trunk? Use a fused distribution block.

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COMMIT YOUR WAY TO JEHOVAH AND HE WILL ACT IN YOUR BEHALF. PSALMS 37:5

Alright, so I'll place the fused distribution block between the amps and the battery that is in the trunk. But those fuses protect the wire correct? I plan on using a 1 into 2 anl fuse block, and my amplifiers have different amp ratings. The MTX is 75 amps while the Kicker requires a 150 amp anl fuse to be wired in line with the power cable. What size fuses should I use in the distribution block?

you should always find a fuse as close as possible to the total of all the onboard fuses in your amp. which would mean for your application an 80 amp fuse for the MTX amp and a 150 amp fuse for the Kicker in the distribution block. Then close to the battery a fuse of 225-250 amps. You should place the fuse as close to the battery as possible. Beings that it in the trunk, which is a crumple zone for most cars, in a rear impact collision an unfused power wire even if its 2 ft long could cause a fire and more damage than what the extra fuse costs.

I disagree with having to fit a fuse - unless the amps do NOT have their own protection fuses.

With some installations, the fuse itself becomes the biggest safety/failure risk - sometimes for physical reasons due to its insertion - see f.ex big 3 upgrade on integra, fuse box? - the 200A fuse on the lower-left of the pic and its cable path.

In those situations you resort to PHYSICAL (instead of electrical) security/protection where you try to ensure a short or fault never occurs - ie, secure the cable and connections, add copious insulation etc. Maybe in hose or conduit, terminal covers etc.

Okay. For the record, I just wanted to use 0 gauge because I thought the more wire, the more current, equals more efficiency. And because the run was so short, I could finally afford to run 0 gauge wire. So I opted to do the fused distribution block. But maybe it would just be easier to run two separate 4 gauge power wires from the battery. One 80 amp fused wire to the MTX 4 channel amp, and one 150 amp fused wire to the Kicker sub amp, and just forget about the distribution blocks. Does this sound better? How would you guys do it? Thanks