You forgot the CLS IIaLOL...the first was CLS, then CLS I, then CLS IA, then CLS II and then CLS IIZ. On these four models, CLS had the horizontal spars, then CLS I and CLS Ia had the vertical sides with the same size, and the CLS II had the left speaker at the out side bigger then the inner side. In other words, you do have left and right speaker with CLS II and up versions...happy listening,Roberto.