I am not sure what you are referencing on this part gotta stress that you have the spl calibrated correctly though right?.
What I was stating was that I setup up the Omni software, play a test tone from my Onkyo which plays an odb tone through each individual speaker and adjust the speakers or subs to 75db using the trim.
I usually shrink the window to center around 60HZ for the subs and 1KHZ for the speakers since that is what they appear to center on and the Onkyo is probably setup to play at those frequencies. I have a little e screen shot attached so you can see what I mean.
I hope that explains it a bit better.
I will be very honest a say I have not researched if the mic stand would cause my reading to be incorrect do to the reflections.
My last few runs I have set the measurement to be all which the manual states as this:
this setting shows a frequency response that includes all room echoes and reflections. In other words, the entire impulse response. In this view, impulse response itself is not shown.
My reason for trying is that I feel that is actually what I am hearing (per say) so why not see what it looks like.