Just got a 2006 6MT and want to add some bass. Does the facotry head unit (no nav system) have outputs for an aftermarket sub/amp or am I going to have to change the head unit? Thanks in advance

 

The answer is contained in many posts here, but I will give you a free fish today

Your HU does NOT have a dedicated sub out. No OEM deck does. However, many subs are added all the time. Do you have a coupe (with 2 6x9 subs) or a sedan (with 1 rear deck sub)?

The Bose amp has an output on the sedan for the powered Bose sub-only amp...

 

Anything is possible if you have the money.... J/K
to answer your question, yes it's possible to install an aftermarket sub/amp combo with the factory HU. You need a some kind of converter but i cant remember exactly what its called at the moment. Any shop that installs car audio will know exactly what you're talking about it you ask, i dont think its too expensive either. The factory HU doesnt have outputs though but with that peice you dont have to get and aftermarket HU.
-GP-