15 inch high power differential drive 1.75 inch woofer tweeter diaphragm compression ring polyethylene box made of birch, black steel surface by sand paint treatment at 90 x covering 40 degree angle design, with axial uniform and smooth and partial axial response of the avant-garde appearance and optimization of power response and vocal frequency performance force sound protection technology SonicGuard can effectively protect the high frequency driver with dust-proof net plane No. 16 steel precise design of protective fence divider, avoid power overload and interruptions