Quote Originally Posted by kexodusc
Nice pictures, but they don't tell us how far apart the sources are, or your relative position to each source, which I believe are key variables. I'd be curious to see measurements with two speakers probably 4-6ft apart at 8-10 ft distnace, taken from the sweet spot?
Measurements taken at the sweet spot are going to be fine. Comb filtering only occurs for off-center listening positions.

The first null in the comb filter occurs when the two signals are offset by 1/2 wavelength. At 1 KHz, a wavelength is approximately 1 foot. So you'll get a 1 KHz null if the difference between path length to the two sources is 6 inches. So, for example, if your distance from the sources is 8 feet and the sources are 1 foot apart, trigonometry tells us the null corresponds to a listening angle of 45 degrees off center. If the sources are further apart, your listening position is closer or the frequency of interest is higher, the sensitivity to listening angle will be greater.