We have lots of experience when it comes to upgrading the audio in any BMW.
Firstly we would recommend replacing the front door speakers (CEN System 1 or 2). Your BMW deserves the best so we recommend either MTX or Focal IFBMW-S, IFBMW-S or 100 KRS Focal specialize in car & home audio so the quality of sound is excellent.
If you also want more volume, control and clarity then (CEN System 3) is for you. Consisting of a 4" Component Speakers paired with a JL Audio XD500/3 3 channel amplifier to power the front speakers and 2x 8" Earthquake SWS-8X subwoofers under the front seats, this is a great upgrade and all from under £1500.
Finally (CEN System 4) Consisting of a 4" Component Speakers, 4" Rear Coaxial Speakers paired with a JL Audio XD700/5 5 channel amplifier with 2x 8" Earthquake SWS-8X under seat subwoofers.
Optional JL Audio FiX-82 OEM Integration DSP with Automatic Time Correction and Digital EQ can be fitted to either CEN System 3 & CEN System 4
*Prices are car dependent and subject to inspection prior agreeing the final price.
**Tweeter mounts maybe required at additional cost.
***All parts can be supplied if installation is not required.Demo Car