From start of production through 05.06, loudspeakers on the standard "Premium Sound System" and optional "Radio - Navigation system" are powered directly by the radio head unit.
From 06.06 production, loudspeakers on the standard "Premium Sound System" and optional "Radio - Navigation system" are powered directly by the Amplifier R12 (located under drivers seat).
All radio system loudspeaker applications consist of a 3-way system with one bass loudspeaker, one mid-range and one treble loudspeaker respectively in left and right front doors. In vehicle rear, a 2-way system with one bass loudspeaker and one treble loudspeaker respectively are installed in each rear side panel/door.
The standard midrange is:
115mm (4.5") diameter.
40mm (1.57") mounting depth.
The standard Midbass is:
180mm (often refered to as a 7" or oversized 6.5")
55mm (2.16") depth of the standard speaker
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