One of the most considerable aspects of a vehicle design judged by the
customers is the noise level inside the cabin. The conventional method is the use
of absorbent materials as the noise absorber e.g. foam and other porous
materials. These materials are usually made from synthetic and are therefore not
environmentally friendly. Moreover, they can be easily dirty or damage and give
bad odour due to smoke or moist. Since the microperforated panel (MPP) has
been investigated to have a good performance as the sound absorber, there is a
feasibility to implement such a panel inside a vehicle cabin. The MPP which is
constructed from a solid panel will provide a hygienic and a non-abrasive
material. Its optically attractive surface will also enhance the art in the cabin
interior. This paper is the preliminary study to investigate the performance of a
double-leaf solid and microperforated partition (SMPP) in terms of its sound
transmission loss (STL). The mathematical model for the STL is derived. The
result shows that the performance substantially improves at the troublesome
frequency the so-called mass-air-mass resonance which occurs in the
conventional double-leaf partition. This is important particularly for the noise
source predominant at low frequencies. This can also be controlled by tuning the
hole size and number as well as the air gap between the panels
