Annoying sounds from cars at stop light

aboogaard said:
"And if it takes 28 feet for the sound to "develop", why can I here that 22Hz note in my 19x15 livingroom so well?" 

Actually I said "fully develop". Very satisfying results can be had with 1/2 or 1/4 wave. For example 12ft. for a 40Hz note will sound fine, I doubt one could really tell the difference, however if one reduces it to a 1/4 wave 7ft., it might not be as authentic sounding. Your 22Hz tone (if authentic), in your room, would be somewhere between 1/4 & 1/2 wave. You would need plenty of power to get 22Hz for full wave.
There is not much musical content below 26Hz unless artificially generated.

http://www.guitarbuilding.org/wp-content/uploads/2014/06/Instrument-Sound-EQ-Chart.pdf

So here is a point I would like  to make.

I don't think those low frequency really travel through those walls in your home. 

I would offer this, the waves from the driver hit the wall, they cause the wall to vibrate/resonate and because the wall is much larger then the driver it amplifies the sound. 

The real answer is both. Sound waves travel through the walls AND make the walls vibrate. 

For me, louder = better.