A head-related impulse response to describe sound signals in a spatial environment is shown to accurately approximate three-dimensional sound data using limited computations, and can also be transformed for ease of computation. The method includes: winding a prepreg around an inner jig ; stacking a ply on the prepreg wound around the inner jig ; and forming a composite material structure by providing composite outer plates on an outer periphery of the inner jig stacking the ply and mounting divided outer jigs thereon. 3\u2019 can be blue or red depending on the acidity of the soil and the presence of aluminum. The processor sends an electronic signal to the component stimulator.