re: "Sounds" like a ripoff of Macrosonix's invention.
It seems like a very good idea. The sound waves compress the air, heating it up, which is removed, then the air expands, cooling it off. The cycle repeats. Hot air, cold air, hot air cold air…Remove the hot air, keep the cold air.
I wonder if they could do something useful with the hot air. Compressing air can get it really hot. I wonder if it is hot enough to run a steam powered turbine?
Why waste the energy?