Your situation seems to mirror what the article mentioned: A little here, a little there adds up through the chain.

If you have to be 6" away to hear it though, I wouldn't worry about it.

On my pretty busy small-city street, if I have less than 70dB of ambient noise, I'm happy. In my case, I could have a good hum (insert joke here) and never hear it anyway.

::::::: No disrespect to Axiom, but my favorite woofer is my yellow lab :::::::