I bought a 2003 cl type s a year ago and I wanna add a sub woofer to complete the already nice audio system but i've heard there are issues in adding an amp and sub to a bose system because the stereo lowers the frequency when you turn up the volume on the head unit. Any help would be great.

 

I added a sub to my '01 cl type s. Just use a Line Out Converter (LOC) and tap into the rear speakers. It is already crossed over, but it isn't that big of a deal. Mine sounded awesome until I had to take it out to make room. But yeah, you'll be lacking a few of the higher bass notes, but those will be played out of the stock rear speakers anyway.

 

I also have a '03 CLS with a Alpine HU. I use a line converter from Scoche and connect it to the stock Bose set up, sounds decent.