Three questions: 1. Can I replace the head unit with a Bose unit from dealer or a wrecked car? 2. Both the standard and Bose stereos have the same # of speakers. Are they the same speakers, or are they upgraded with the Bose system. 3. Is there a sub-woofer with the standard stereo? If not, is the car pre-wired to easily add one?

1. the bose/non bose head units are the same. So you do not need to replace the head unit, only reprogram it (VAG tool, VWTOOLS, ProTools)<p>2. Check archives. Speaker count may/not be the same, but the bose has an amplifier in the trunk. The entire vehicle wiring harness for the stereo is different.<p>3. Check FAQ. No Bose does not have a sub, unless u have an AVANT, which had a sub in the back. I added a sub to the A4 using the FAQ. If u are not handy with some wiring, don't try it.<p><br>1996 a4 2.8 qms (with sub)

i think in the non bose stereo the speakers are driven directly from the head unit(when you pull it out, its the harness right below the Green/Yellow/Blue one). IN the bose, everything is wired from the back, the head unit just sends preamp signals to a tiny black amp in the trunk.) the speakers are the same in number but arn't bose. i just replaces my 97 bose head unit w/ a nice clarion. THe clarion had NO power output just like the bose headunit, and so i needed an external amp. its nice because all of the speaker wires are in teh back of the care in a brown harness connected to the stock amp.