I'm planning an early christmas present to myself, a 12" sub in the trunk to add to my current aftermarket system. I need to buy some components to hook it all up and I want to make sure I'm doing it right.

I'm currently running an Infinity 5761a to the four 5x7's and the 8" door subs. It is hooked up with a 4ga power kit with a 120A fuse at the battery.

I'm going to add an Infinity 311a to power the trunk sub. I was thinking I need to buy two (one for positive, one for negative) 4ga in/8ga out non fused power distribution boxes in the trunk to split the power to the two amps. Does that sound right?

The max current draw of both amps combined is 127A. Should I upgrade to a 150A fuse, or is the 120A ok?

Should I look into adding capacitor? What size?

I'm trying to be brief, but if you need more info just ask. Thanks for your help.

 

You have everything correct, and what you are planning will work just fine. Also, remember that the fuse rating should always be the max draw of the wire (or less), not the components. You're good.

 

Thanks. I should just PM you.

Any thoughts on a capacitor? I'm probably not running enough juice to really warrant one.

 

You won't need a cap- they're useless in a daily system anyway. If you get a proper ground, you could double your amps and have no dimming.