A new innovation in every driver replaces the usual rigid coupling of driver and voice coil with a pliable one. This ‘Dynamic Coupling Filter’ is a nylon ring ingeniously calibrated to be rigid up to the crossover frequency, and to act like a spring above it. In so doing the DCF helps to dampen surplus high frequency energy produced by the driver. It’s also perforated to encourage voice coil cooling and release air pressure from behind the cone for maximum driver efficiency. Result: more natural sound.