This page describes the different Speaker options available for the F30 series BMW.
This is the default speaker system in most regions
Basic has 6 speakers
Option Code: 676
This is the default speaker system in North-America
HiFi-loudspeaker system with a 205W Amp, equalizing tuned to the car, and 9 speakers
Option Code: 698
Harman Kardon Surround Sound System, with a 600W digital Amp and 16 speakers