Sometimes you only have room for a single speaker. Unless your amplifier has the ability to sum the left and right channels (mono), you're stuck choosing between listening to the Right channel or Left channel of a stereo recording.
The SDX-S65 solves this dilemma. It is designed with a dual-voice coil woofer and two independent tweeters. Simply run cable as if you were connecting one pair of regular speakers (i.e. use a single 4-conductor cable or use two 2-conductor cables). The SDX-S65 includes two sets of binding posts for connecting both the left and right channel.