patrick2

I know, there are tons of threads on here already about installing a system. I've read as much as I can take with no one addressing my question: has any one already, or at least have an opinion on, tapped the power line to one of the pre-existing amps for an additional amp (for a sub).

My guess is the pre-existing wires wont support the new power requirement. But I felt I should at least see if anybody had done this.

Now taking all replies...

Hayabusa02

As far as I know the guage wire is far too small for a sub amp. I ran 4 guage for my sub amp. You shouldnt take the easy way out on this one.

patrick2

Yeah, I ran a power cable from the battery, after looking at the Bose power wires youre def right, they are really small, as are all the wires they used, I had to get the quick connects somebody referenced to connect to the speaker wires, they have to be at least an 18 gauge.

Tuckermaclain

Because of the low voltage you are working with you need a lot of current to get to a specified wattage. Here is a nice chart from an engineering handbook. If you don't want to read it, just use a 4ga line like everybody suggests.

American Wire Gauge table and AWG Electrical Current Load Limits with skin depth frequencies

As far as speaker wires go, a great way to waste money is a premium speaker wire like Monster Cable. I have always used lamp-cord type wire, usually 16ga. Just as good at 1% of the cost. Spend the rest on better equipment or take your wife out to dinner. Here is a beautiful article on speaker wire from a former chief engineer at McIntosh, maker of premium audio equipment:

Speaker Wire

Hope this helped.

roots4x

Yeah, running the power cable is the biggest PITA. Once you do it though, you're set. I'm probably not going to run a cable in my new car, but my old G35 coupe I ran and it really wasn't as bad as I thought it'd be. PITA for sure, but doable.