question about wave loading into RTA window

[teyhyrh4r]

is it broken, or am I not doing it right?
this is a IR of to EQ filters close to 0dB imported with fft 32k:

here 64k

as soon as I make FFT higher nothing will apear.
does that have something to do with the levels?
why do the levels even differ on the 2 that ploted?

 

[John Mulcahy]

The spectrum plot shows you the level in each frequency bin of the FFT. The more bins (i.e. the longer the FFT), the less energy there is in each bin.

If you want to see the response of the filter impulse response import it on the main REW window, not in the RTA. You can drag the WAV file onto the main window to do that.