Door Audio Response Hybrid Modeling and Assesment 2017-01-1849

The door response to audio excitation contributes to the overall performance of the audio system on several items. First, acting as a cabinet, it influences the loudspeaker response. Second, due to the door trim inner panel radiation, the radiated power is disturbed. A third effect is the regular occurrence of squeak and rattle, that will not be considered at this stage. Design issues regarding these attributes are numerous, from the loudspeaker design to door structure and trim definition. Modeling then appears as an unavoidable tool to handle the acoustic response of the loudspeaker in its actual surrounding. Since most of the issues are related to low frequency excitations (<200 Hz), and considering the fact that several loudspeaker references may be used in the same door, it was chosen to model the system in a hybrid manner: the electro-dynamical behavior of the speaker is modelled using a classical 1D modelling (Thiele and Small) while the door vibro-acoustic behavior is modelled by means of Finite Elements. After the vibroacoustic coupling between the loudspeaker and the door is fully described, transmission paths are investigated, showing possible simplifications. Electroacoustical indicators are then proposed to control the door design regarding audio quality issues. Sensitivity of the indicators to some design variables will then be shown.