Voila
SPL and distortion window
SPL window gives about 90dB.
Distortion window is more like 70dB for the fundamental.
Distortion (dB SPL) is at around 30-40dB or about 30-40dB below the fundamental.
How is the fundamental defined? Apparently adding 30-40dB of distortion to 70dB fundamental does not give the 90dB in the SPL window...
Thanks in advance
I've never seen that either, John would be best to chime in on this. The distortion plot is clearly wrong as it shows your noise floor as residing near the residual of the electronics practically. If you actually had a room that quiet, you quite literally would have built an anechoic chamber. Having a noise floor below 10db's (even 0db's at places) is what test facilities go for (and many don't achieve). It appears that you could add 20db's to each of these values and get you back where you should be.
Is there any chance you accidentally applied some shift to the amplitude? Is this shift always present in every measurement no matter what you do? Like if you took 5 measurements in a row, don't touch anything, go straight to the distortion plot, it would show that same behavior?