Acoustics do affect all frequencies but in different ways. With the high end you are correct the waves will reflect off walls and can cause a "harsh" sound or muddy the sound up, but this is not the same as what happens with lower frequencies. When one hears muddied dialog or a harsh sound this is from the same signal produced by a loud speaker hitting various reflection points then being reflected towards one ears at slightly different time. The brain has trouble separating all the information and it becomes muddied.
Swed mentions the low end where room nodes (specifically how sound waves interact with a given room) play more a role in completely canceling the waves out or making them double up on themselves.
The reason different frequencies respond differently to rooms is caused by wavelength.
Again if I made any errors someone please make me aware. I have been reading up much more on the technical side to this hobby but might have misunderstood something in the journals/books I have picked up.
Depending how everything goes I might, but there is no sense in making a new thread or hiding the real point of this thread midway through. I probably will end up doing it either way though. Maybe I'll just ask a mod to move it once I have made the changes
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