Below some curves showing the effects of:
A) using a 4k MLS sequence or a 16k MLS sequence.
B) full inroom (85millisecond time interval analyzed) with 4096 point FFT
or echoes gated out by using a 1024 point FFT spanning 21 milliseconds.
The white and green plot are both 1024 point FFT's, one on a 4k MLS, the other on a 16k MLS The difference is visible in the low end of the spectrum. The yellow and brown curve are both 4096 point FFT's showing increased resolution for both the 4k MLS and the 16 k MLS record. The difference between 4k and 16k MLS is again visible in the low end of the spectrum. Curve smoothing was in all four cases set at 1/12th of an octave.
These plots were taken in between some testing on a dipole RD75 at 2 meter distance, in search to duplicate John's "bump". The same effect is visible on one of my previous dipole Carver plots, to be found under the "waterfall" plots on a dipole Carver.