Hello, since I want to have a nicer sound with a little more bass in my S40, but this one only has the normal performance radio, I would like to exchange my 4 loudspeakers in the doors. Now you ask me the question which one I should build, and since I have no idea about it I have found out here that it is 16cm loudspeaker and I need such distance rings (for the installation depth…). Which one do I buy? 2-3 way loudspeakers? which brand? Price up to 200Euro (4 speakers + 4 holders) I thank Fabian already