A system is disclosed for reducing the transmission of acoustical energy between a first and second wall surface of a wall comprising a first and a second beam for supporting a sound panel. Each of the first and second beams comprises first and second flanges interconnected by an inner connector with a fold defined in the inner connector for reducing the transmission of acoustical energy between the first and second flange. The fold cooperates with one of the flanges for defining a pocket for receiving an edge of a sound panel. The first and second flange support the first and second wall surface of the wall with the sound panel.