I have a 06 mustang with a shaker 500 and would like to add on my subs from my old car. Is there any way to hook the subs into the shaker 500?

 

yep..

 

Do you need to buy a special adapter from the dealership or from store?

 

some amps will have an input section that is labeled "high input". This is made to be connected straight to the speaker wires on your existing stereo with out any adaptor. If your amp does not have this option, or if you do it and it makes noise then you need to get what is called a line output converter(LOC). This will connect to your factory speaker wires and will then allow you to run an rca cable from the loc to the amp.

 

Thanks for the help, I'm going to try it.