A driver assembly, comprising: a housing structure ; a magnet assembly within the housing structure and comprising: a permanent magnet ; a plate structure underlying the permanent magnet ; a voice coil circumscribing the permanent magnet and the plate structure ; a yoke structure at least partially surrounding the permanent magnet , the plate structure , and the voice coil ; and opposing spring structures coupled to the housing structure vertically offset at different vertical positions from one another and configured to impede horizontal movement of the permanent magnet , the plate structure , and the yoke structure while permitting vertical movement thereof; the driver assembly characterized by : a tubular structure provided within and vertically extending through aligned, centrally horizontally positioned apertures in the opposing spring structures and the magnet assembly and coupled to the opposing spring structures , wherein the tubular structure exhibits lateral projections at opposing vertical ends thereof, and the opposing spring structures are attached to the lateral projections. a housing structure ; a magnet assembly within the housing structure and comprising: a permanent magnet ; a plate structure underlying the permanent magnet ; a voice coil circumscribing the permanent magnet and the plate structure ; a yoke structure at least partially surrounding the permanent magnet , the plate structure , and the voice coil ; and opposing spring structures coupled to the housing structure vertically offset at different vertical positions from one another and configured to impede horizontal movement of the permanent magnet , the plate structure , and the yoke structure while permitting vertical movement thereof; the driver assembly characterized by : a tubular structure provided within and vertically extending through aligned, centrally horizontally positioned apertures in the opposing spring structures and the magnet assembly and coupled to the opposing spring structures , wherein the tubular structure exhibits lateral projections at opposing vertical ends thereof, and the opposing spring structures are attached to the lateral projections. a permanent magnet ; a plate structure underlying the permanent magnet ; a voice coil circumscribing the permanent magnet and the plate structure ; a yoke structure at least partially surrounding the permanent magnet , the plate structure , and the voice coil ; and opposing spring structures coupled to the housing structure vertically offset at different vertical positions from one another and configured to impede horizontal movement of the permanent magnet , the plate structure , and the yoke structure while permitting vertical movement thereof; the driver assembly characterized by : a tubular structure provided within and vertically extending through aligned, centrally horizontally positioned apertures in the opposing spring structures and the magnet assembly and coupled to the opposing spring structures , wherein the tubular structure exhibits lateral projections at opposing vertical ends thereof, and the opposing spring structures are attached to the lateral projections. a tubular structure provided within and vertically extending through aligned, centrally horizontally positioned apertures in the opposing spring structures and the magnet assembly and coupled to the opposing spring structures , wherein the tubular structure exhibits lateral projections at opposing vertical ends thereof, and the opposing spring structures are attached to the lateral projections. <EOS>