Much time was invested in the research of the perfect material for the C 165 woofer cones: through a long process of customisation of the materials SPP-M was selected (Semi Pressed Paper-Mica), which preserves the natural sound of the semi-pressed paper and enhances it with Mica powder improving rigidity. The result is an excellent balance between lightness and damping, essential for a powerful and controlled emission. The oversized ferrite magnet provides excellent control even at higher excursions.6