So you are telling me that you need a new housemate
Ringing is typically a higher frequency phenomenon. So if this treatment is intended to rectify ringing, you would have to use test tones above 300Hz. Whatever effects are evident in the time domain are also evident in the frequency domain. So you should still be able to measure the improvement by placing a meter at your listening position and recording the SPL for various test tones with and without the treatment.
Of course if you have better things to do, I understand