CSB SPEAKERS FOR BMW. Time to say goodbye to your ex-factory sound! All models are equipped with a stable, nevertheless ultralight fiberglass cone and feature a dual neodymium drive with solid N42H magnet. This allows optimum sound even with moderate amplifier power. The CSB8W subwoofer is equipped with a 50 mm CCAW voice coil, which – due to its lightweight – achieves an amazing efficiency of 89 dB / W / m. The 25 mm tweeter of the component system CSB4.2C comes with a high-class titanium dome and also a powerful neodymium magnet drive. Both ensure linear frequency response up to over 20 kHz and a fantastic treble resolution. All models have vehicle-specific connections for easy installation. 20 CM (8) SUBWOOFER PAIR FOR BMW E / F / G MODELS. 180 Watts/RMS, 300 Watts/MAX. Frequency Range 30 – 300 Hz. 50 mm (2) Voice Coil. Fiberglass Cone, Nomex Spider. Installation Depth 31 mm. Installation Opening 192 mm.