The PP/TPX based cone matches ideally with the adaptive rubber surround. The result is an outstandingly smooth frequency response from the mid woofer. The coaxially arranged precoated fabric dome high frequency unit has a low resonance frequency, and integrates with the cone driver to a point source. The cone of the woofer acts as a horn loading for the tweeter, and the chassis of the dome unit represents the throat of this horn. 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.