Speaker unit is the large diameter super woofer for the ultra low frequency reproduction. Its hi-rigid diaphragm consists in the radial paper making technique and whizzy hybrid material realizes the ultra low sound reproduction, people have never experienced. FW800HS also employs the following specialized parts for the realistic low sound reproduction. Highly durable diaphragm & cap. High input 4-layers voice coil. Large aluminum die-cast heat sink. Push-pull double spider. FW800HS’s acoustic parameter is tuned can be worked with the smaller enclosure - 500 liter.