Paul810,

I'm sorry Bagheera, but I believed it was just the opposite: the higher the tone, the farther it carries. Higher tones are also more distinguishable from ambient noise like traffic.

I recall trying out how far the sound of my cousin's Casio sportswatch carried underwater in a pool, the high tone was audible 20 m away. Of course that's underwater. But in the open air, I believe it's just the same. Although all people are different, higher tones are generally heard from farther away.

As for radio waves Bagheera is right, lower frequencies are carried further.

Sorry to mix you up like that. Please get a third opinion <img src="images/graemlins/smirk.gif" alt="" />

Luca