i`m not sure if this 100% true as i have a 06 300c with these badges on the sides of the doors. and when i installed my gps antenna i put it directly under the center speaker grill cover,due to there not being a speaker there. :dunno:If you have a little Boston Acoustic badge on the front corner of your driver and passenger door, you have the upgraded BA7 system, which means all three speakers across the dash, two in the rear deck and one in each front door (thus "7") plus a more powerful amp (370 watt if memory serves).
If you don't have the badge, then you may have a center speaker grille in the dash, but you probably don't have a speaker behind it, and your amp is about 270 watts.
SEARCH function rules as usualout of curiosity . where is the amp located ?