I have the regular PCM system and would like to add a subwoofer. I've seen one post where someone attempted this with line level inputs. My question is can you add a bose factory subwoofer (if you found one at a salvage yard or eBay...) to a regular PCM system? And if yes how easy is it?

 

Ummm... you ought'a add you Cayenne to your sig so we don't have to ask what year.. and what's a "regular" PCM? Non-Bose/Burmeister?

Dunno - I'd suspect the simple answer is no - since the amp for the subwoofer is connected via the MOST buss system. https://en.wikipedia.org/wiki/MOST_Bus but mebbe you can add it if the "regular" PCM uses MOST.