A trim panel assembly for a vehicle incorporates a flat panel speaker. The trim panel defines an interior surface of a passenger compartment of the vehicle and has a speaker aperture with a peripheral edge. A diaphragm panel is disposed in the speaker aperture with a trim face and a rear face. A flexible surround joins the diaphragm panel to the aperture edge so that the diaphragm panel is movable along an axis of the speaker aperture and so that vibrations from the diaphragm panel to the trim panel are damped. An exciter receives audio signals for reproduction. The exciter has an actuator suspended in a housing. The actuator is fixed to the rear face of the diaphragm panel. A support bracket spans the speaker aperture and has first and second ends affixed to a rear side of the trim panel and an intermediate point affixed to the housing of the exciter.