im wondering if its a good idea to hook up a 10in rockford fosgate sub to my stock stereo?

 

No

it's not. You can do it but almost not worth the effort.

Is there a reason you cheaping out and doing it that way?

 

And it depends what you mean By "hook up to stock sterio"

 

im not doing it i was just wondering cause im still looking for a cheap stereo

 

i meant factory stereo

 

Yeah, It requires an LOC though. LOC = Line Output Converter. It will take and convert your speaker wires to RCA outputs.

Most common option is running it off of the rear speakers. I would hook it up right behind the radio itself and zip tie it to something behind there. Then you would just need to run RCA's to the trunk and plug them into the AMP.

Splice turn on wire to the gray wire
LR + is Brown, - is Yellow
RR + is Red, - is White

Would be a whole lot easier though if you just bought an aftermarket deck.