Lack of bass in one area - I am only asking why

#1

Hi everyone

That's the first floor of my townhouse. It's a HW floor supported by joists, and the basement is underneath. The pic is not exactly to scale, but close enough.

I have a Conrad Johnson pre, an old B&K power amp, and B&W speakers:

http://www.hifi-review.com/151906-b-w-dm605-s2.html

I have a good amount of low end from this system, which is audible everywhere in the space, including areas: X1-4, and Z1&2

When I move into the area depicted by Y1&2, the low end all but disappears. I think this is considered a null?

The Q is why does this decrease in low end happen in that area? Not that I am looking to do anything to fix it; I am not, as there is no need. I am simply curious about the science behind what is going on here.

Thanks in advance.

#2

two things - one, the large opening is allowing the LF energy to leave the space, and two - the two short walls are likely creating a null between them for a very small range of frequencies which are likely the LMF frequencies.

#3

Cool - thx

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