The center of the 2405 is 6" above the top surface of the 2397 horn. The positioning of the individual speakers just kind of evolved. I had read that 2 identical speakers should normally be placed as close to each other as possible. However this requirement is not as critical for low frequencies. Separating the 2235 speakers to the top and bottom positions allowed me to place the 2397 horn at optimal ear level (42 1/2"), Westlake tower speakers frequently place the UHF driver below their midrange horn however I just didn't like that look and felt that would place the UHF too low. The chamber for the 2202 has the exact dimensions of the original 4355 cabinet, and the volume requirements for the 2235 speakers (about 5 cu ft/speaker) mandated the height of that section of the cabinet. The 2441 driver is also mounted in a wood cradle that raises it about 1" off of the partition that it rests on. I have included a photo of the mount before cutting it from the plywood stock.