Originally Posted by shrink
Don't think the e90 ever had "business" speaker system. That's a name that's being attached to newer models.
There was base system, hi-fi loudspeaker system, logic 7/hk, and individual.
I have the hifi system, and overall, find it excellent. The only real limit is the lack of more precise EQ that the l7 system has. But considering adding one of these jbl ms2 boxes to fix that.
Most of german cars come with some sort of processing and time alligned algorithm. Hi-fi is pure stereo. As you said, MS-2 should address the time allignment way better than BMW default processing of base / hi-fi system.