Im looking at upgrading my car to a A6 as Im needing a bigger car now the kids are getting bigger. Ive currently owned my a4 for 8 years and its been a good car the sound system in my opinion has been great as I do like my music and couldnt get a inferior sounding system I was fancying a 5series but the shockingly bad sound system steers me away. My a4 has the standard audi chorus with rear amplified door speakers and rear sub woofer built into parcel shelf what does the a6 sytem consist of and does it have a sub on rear shelf. Id love bose but ive never seen it in a 09 10 plate car. Any info would be appreciated.