This paper discusses the modeling of the vibration and acoustic responses of sandwich composite panels with attached sound packages, using both analytical and numerical methods. Special attention is devoted to the modeling using the transfer matrix method of these structures in various mounting conditions (single wall and double wall) together with the calculation of various vibroacoustics indicators (vibration response, radiated power, transmission loss, added damping, air-borne insertion loss, structure-borne insertion loss, etc.) under various excitations (acoustical, mechanical, and turbulent boundary layers). Examples are presented to compare the performance of the presented models and demonstrate their range of applicability and usefulness.