Classical hand-coated paper cone and matching natural rubber surround produce a well-behaved roll-off characteristic and reduce potential resonance problems. Long, high-temperature voice coil wound on an aluminium voice coil former gives low distortion and high power handling capacity. Large magnet system provides high efficiency and good transient response. Bumped backplate in the magnet system allows maximum utilization of the long voice coil without mechanical limitation. Extremely stiff and stable injection moulded metal basket keeps the critical components in perfect alignment. Large windows in the basket both above and below the spider reduce sound reflection, air flow noise and cavity resonance to a minimum.