I'm replacing speakers in an '11 Golf TDI. (I think it's the RCD-510.) The stock system isn't bad, but a bit harsh at times, and seems like reaplacing the speakers might help. See this thread on a similar topic: http://forums.vwvortex.com/showthrea...+speakers+bass
So, I replace the passenger door speaker (Polk Dxi 6500), and.... what happened to the bass? It turns out that the stock speakers have a big boost in bass. This probably can be compensated by boosing the bass control. The other problem I have is that my replacement speakers are supposed to go down to 35hz, but they don't have much low output until maybe 50hz. Is there active EQ in the head-unit affecting this? Or a case where they designed the stock system to have big boom, and putting in "correct" speakers sounds weak in comparison? Does the RCD-510 have a hidden EQ menu?
Meanwhile, the mids and highs are better with the replacement, but not as much as I would have expected. The new tweeter is a lot smoother. Well, I'm going to finish the driver door, and see what I can do with the head-unit settings.
By the way, I found several DIY pages on door removal, and each one has its own tidbit of info. Things are easier with a complete understanding, but one page will not do it!