This topic seems to be popping up a lot recently..."near field vs far field presents a completely different frequency response to the ears/senses."
that is the understanding many folks have. however, it is inconsistent with what folks experience. nearfield bass (less than 1 meter) is more tactile than farfield bass even though the reflections from room gain dramatically increase the measured spl in the farfield.
to properly measure the nearfield experience (at less than 1 meter), it may be necessary to move toward a more complete measurement system that considers sound "intensity" as somebody already mentioned, but I'm not even sure if *that* goes far enough.
we don't have enough data to know and the science isn't even very well understood. the paper that i linked to is a 2014 publication citing 28 other studies on the matter (sound behavior in the nearfield) and there is no consensus on what is going on in the region of space very close to the source.
I'm surprised it doesn't come up more frequently, as doing it correctly, really adds another level to the ULF experience. If PVL (Particle Velocity Level) varies with different designs and drivers (which I believe it does), it's brings a whole new dimension to subwoofers that has not really been explored.
Sound Intensity Meter - MicroflownWhat sort of measurement system includes intensity? And how much is one?
Yup, sounds right. PVL is the game changer in the nearfield. I indirectly measured Sound Intensity here using an accelerometer.Great link LTD02.
My initial tl;dr takeaway as it applies to the topic at hand is that, a good portion of the nearfield sound intensity ("reactive intensity") is a vector quantity where pressure and velocity are 90 degrees out of phase and so, while being very much real and contributing to the user's experience, it doesn't radiate out into the room and doesn't sum with the scalar quantity know as "active intensity" in a straightforward way, so SPL measurements don't show it. Sound about right?
Also here's a link with purty animated pictures that show some of this stuff, still trying to wrap my brain around it all: http://www.acs.psu.edu/drussell/Demos/Burns_PhD_animations/Burns_PhD_anim.html
Like LTD, one of my sources was that B&K doc. I also have several other sources listed in that post.