Due to a technical problem in the 4 story building I live in, everyday walking becomes amplified through the floor into my apartment as low frequency booming.
I need to create proof in order to get the housing company to make an improvement to the insulation. In terms of housing this seems to be a rather grey area. It's a bit like air pollution, in the sense that people can smell it but are not able to provide proof.
After many attempts with recordings, all devoid of the sound I need to capture, I used a spectrogram app (Spectroid) and noticed that the sound I need to capture is between 20 and 50Hz, which is too low for my devices.
I've now borrowed a better recorder, and in my DAW (ableton) I can see the presence of the low frequencies, but this is useless as proof because most devices wont manage playback.
After discovering this I'm trying to think through what might be happening, and where the technical faults might be. I imagine that the nature of the solid floating wooden floor upstairs, in relation to the size of my space (soundbox) is causing these low frequency physical booms. I think maybe the wooden floor upstairs might also be acting as a drum membrane.
I've done a sound design course but my knowledge is limited. With google I learnt that these lower frequencies have a proportionally higher SPL than "normal" frequencies, and that because they are so physical, they resonate in the body (and ears), having a large annoyance potential. Also that these frequencies require a different insulation material.
In a nut shell, do you have advice that can help me create convincing proof for my argument. My budget for this is also very limited.