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Discussion Starter · #1 ·
Hello everyone.

Okay, so after watching a friend hook up my previous system, I decided to try it myself. That was a while ago..and it wasn't exactly neat and proper.
Now, I'm upgrading everything else except the amp and sub, which is a Kenwood KAC-9105D mono, and Polk DB1222. I'm adding a 4-channel amp (alpine mrp-f300).

What would be the best way to connect the two amps and the stiffening cap together?

The Kenwood is supposedly 900 watts RMS..but I read some where that amps generally put out about 70% of what they're rated. Is that true?
The Alpine is 200 watts RMS. I'm using 4 gauge wire right now, would I need to use a lower gauge?

I was thinking this: 4 gauge from battery to a distribution block split near the amps block (KNF-23) , 8 gauge wire from the block to mono amp + capacitor, 8 gauge from the block directly to the 4-channel amp, 8 gauge connecting amps to ground block (KND-23), and 4 gauge for the ground point.

Thanks for any help!
 

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Use a fused distro block, run the 4ch directly to it and the mono trough the cap to it.
A cap is only useful (if it's already useful) if it's connected as directly as possible to the amp that needs it.
This is only possible if there are no fuses between that amp and the capacitor, but since every power wire needs its own fuse, there is no way to connect 2 amps to 1 cap in a secure way.

A 200W RMS 4ch amp driving speakers will never need a cap. A 900W RMS mono, well, actually it doesn't need it either if everything is alright, but it'll have more use of it...

Isabelle
 

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Use a fused distro block, run the 4ch directly to it and the mono trough the cap to it.
A cap is only useful (if it's already useful) if it's connected as directly as possible to the amp that needs it.
This is only possible if there are no fuses between that amp and the capacitor, but since every power wire needs its own fuse, there is no way to connect 2 amps to 1 cap in a secure way.

A 200W RMS 4ch amp driving speakers will never need a cap. A 900W RMS mono, well, actually it doesn't need it either if everything is alright, but it'll have more use of it...

Isabelle
Wait...what? I don't want to go into the effectiveness of a cap, but I would put a fuse on anything that stores/produces power. What would happen if the power lead came loose from the amp and touched metal?
 

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The cap would unload in less than a second and then the fuse that's before the cap will blow.

I totally agree on you if you're talking about an alternator or a battery that's able to produce a high current for a reasonably long time when shorted.
A cap is very fast and can deliver high peaks of current, but it won't do this for a long time.

Off course the best thing you can do is:
- make sure the cables can't come loose
- make sure, if a power cable can come loose, it won't touch metal or some other grounding point.

Isabelle
 

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Discussion Starter · #7 ·
What gauge wire should I run from the battery to the block, and block to amps?
My lights still dim even with the cap hooked up.. Battery upgrade is part of the "big three", right? Is there a certain kind/brand of battery people use?
 

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4 gauge from the battery to the block and 8 gauge to the amps will work without any issues. The big 3 typically refers to upgrading your wires, chassis and engine ground and the alternator to battery wire. I'm a supporter of upgrading grounds, but honestly believe the alternator to battery wire is a waste. Upgrading your grounds may help, but you aren't running a lot of power, I think that a good battery is a must. Upgrade the grounds and see how things go. The next step would be a new battery.
 

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If I were to add a cap (I won't because (a) I'm too cheap, and (b) I have no room in the engine compartment for one), I would hook it directly to the constant 12v junction box under the hood. This is generally the closest (electrically) to the headlights you can get it, and therefore the most effective at reducing dimming.
 

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If I were to add a cap (I won't because (a) I'm too cheap, and (b) I have no room in the engine compartment for one), I would hook it directly to the constant 12v junction box under the hood. This is generally the closest (electrically) to the headlights you can get it, and therefore the most effective at reducing dimming.

I never thought about it like that before, but that makes a lot of sense. Not that I ever plan on getting a "cap", but still.
 

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Wiring your sub at a higher impedance is the same as turning your volume down. If your lights are dimming, it means your amp is drawing a lot of current. Amps have to draw a lot of current to produce a lot of power.
 
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