Thank you very much Mathieu. I’m learning and appreciate the guidance. I was going by the earlier ref web page for 4 seconds which has the following text:
How do we define the optimal window duration then? A commonly used approach is to take a window sufficiently long to encompasses at least two full cycles of the lowest frequency of interest. In our case, our lowest frequency of interest is 0.5 Hz so we will choose a window of 2/0.5=4 seconds.
with 0.5Hz being the configured minimum for delta band.
I’m open to other views and ideas - thank you again very much.