This paper is concerned with the evaluation and analysis of the pressure field around the observer point inside a three dimensional rectangular enclosure. This is performed by simulating the enclosure using a vibro-acoustic finite element model. The sound field inside the enclosure is the result of excitation of a periodic primary sound source at low frequency and secondary cancelling sources designed using local active control method. The acoustic environment of the enclosure is modeled using the finite element method which is bounded by five rigid boundaries and a flexible plate on the top side. The modeling and analysis of the natural frequencies of the vibro-acoustic model was performed using COMSOL Multiphysics® software. Comparison of the results with related published analytical and experimental works validates the finite element model. The result of the local control shows a good minimization of the estimated potential energy.