Richard Clark wrote:

Contrary to the implication of Tom's tree falling unheard in the
forest, no I am not suggesting that. If one plants a load at a
distance and ignores it; then, yes, interference occurs. Remove the
load, and you remove interference.

So I gotta ask: what do waves do instead of superposing when there
isn't a load somewhere? Whistle and look the other way? :-)

73, Jim ac6xg