Here is the idea I came up with: I have generated 1ms sine tones at various frequencies at a certain volume and the same at a volume 30dB lower

Then I play these right after each other, first the loud one then the quiet one and I measure the response with the Logger feature of the SPL meter in REW (using C weighting and Fast mode)

I have generated these tones at 30, 40, 100, 440, 1000 and 7000Hz and I have also done the same with full range and limited range (500-2000Hz) pink noise

In all measurements I could see a dynamic range between 25 and 29dB so pretty close to the 30dB difference

Some examples:

40Hz

1000Hz

PN full range

I would like to ask if this makes sense and if there are better ways to measure the same?

Many thanks in advance