I love the stock radio in my mini its perfect for my needs. Only thing missing is alittle bass. I want to add 2- 10" Sub woofers to the stock system. Is this possible and if so what will it take. Obviously, subs, box, amp, and sub wiring kit. How would I connect it to the stock head unit though?? I already have the subs and box, btw.
Thanks!

some amps have high level inputs which are speaker wire inputs to the amp instead of using the rca inputs and if it doesn't you can go to your local stereo shop and get a high level to low level converter ( speaker wire to rca converter) then tap it of of your rear speaker wires then run your rcas from there to your amp. i know metra make a converter but there are other companies.

I like how the r56 system sounds already, but I want more bass as well. I'm planning on adding an amp and a 10" sub in the trunk once I take delivery of my MINI. I'm going to let the professionals do it though. I know it's doable. Here is pic I found on the MINI2.

You can either buy an amp with line level in (hi) or get a Line level converter (either an inline one for $10 or a powered module with gain controls for about $30).....

Thats one of mine above
I usually hide the amps but that car was so highly specced I ran out of room
I allways use kenwood amps with high level inputs & hide them under the front seats or in the left boot cubby

You did a very good job. Too bad you're not located in the States.

The Infinity BassLink has been a popular sub to add to the stock system.

wat a conicidence... i happen to have 2 10" infinity basslinks for sale... haha