Hi Chris, The horn is not in the centre imply because it will not fit any other way, in fact the side wall of the box had to be ground down to about 6-8mm thickness just to get the compression driver in.
When you array any two horns you generally find there are some issues. If you array this box at at total of 60 degrees there is a little bit of a drop with the HF in the middle; 50 degrees seems to work quite well without too many issues, its not perfect, but much better than most, and the two 12" drivers seem to combine very well.
In this case the pattern is somewhere around 110 degrees for two boxes (60 + 60 - 10 degrees of overlap), you can of course open them up a little to give a total coverage of 120 degrees but its not as even.
The idea was a general purpose small light 60 degree box that could be array if needed and still work well.
