The C5-650X, along with the component equivalent C5-650, are the mid-size speakers available in the C5 evolution line. The 6 1/2" woofers have a mineral filled poly-propelene cone, Butyl rubber surround, 1" voice coil and are mounted in a cast alloy frame using JL Audio's patented Elevated Frame Cooling. The 3/4" silk soft dome tweeters are powered by a Neodymium Magnet and use ferrofluid cooling and damping. This tweeter is universal accross the entire C5 series. The two included 2-way crossover networks use a 1st order low-pass filter and 2nd order high-pass and comes equipped with a 4-position adjustable tweeter output level, 3-position midrange presence control and features Polyswitch tweeter protection. Much like the tweeter, this crossover network is included with all C5 speaker sets.