Motor Sound System

Motor Sound System (MSS)

The Motor Sound System is a membrane system for modulating and transmitting the
intake
system pressure pulses to the passenger compartment. This generates a sporting sound
that is typical of a roadster.
In this market segment, BMW is the first manufacturer to deliberately transmit pressure
pulses from the intake system to generate sound in the passenger compartment. The MSS is only installed on the M54B30 engine.

- Connection of MSS at front bulkhead
- Housing
- Upper support
- Lower mounting
- Connection to the intake system

Structure of the Engine Sound System (MSS)
The sound generator is connected by a membrane (2) to the column of air in the intake manifold.

The pressure pulse is transmitted into the passenger compartment via this membrane,
which also ensures a "sealed" intake system.

A clamping mechanism ensures a constant preload on the membrane for even acoustics,
balancing out temperature and material aging influences on the membrane. The tensioning spring generates an axial motion of the plunger by turning the rotating element.
The plunger continuously tensions the membrane.

Note: There are foam inserts in the sound channel.
These must not be removed during repairs, because the noise generated in the vehicle
interior will increases to an unacceptable level.