Graph below shows the first magnitude/frequency plot I performed on the box. This measurement is in a carpeted room (22' L x 14' W x18'H) The microphone was positioned in such a way that there was no reflection from the patio door behind the microphone. Just left the door open. Most reflection were 20 dB down from the first pulse response.
No sign of dipole baffle low cancellation but the dip at 1300 Hz was bothersome until I looked at the wavelength this represented. The driver was mounted in front of the box to make it easily replacable. This left me with a baffle that was not particular flat. Total box width is 8 1/2". I built the front of the box up so that the baffle is totally flat and this dip is pretty much gone.