These speakers were designed in order to reproduce the very first octaves of the audio spectrum with precision, impact and power, with minimum size requirements in any configurations. HX line features double voice coil models, which permit to have a more flexible subwoofer section. This way you can handle connections and the number of speakers you need in order to take full advantage of the amplifier you are using. Double voice coil, i.e.: double power, double efficiency, smaller enclosures. The best solution to every need and very low bass, able to meet any expectations.