I just did a quick calculation. Assuming I didn't screw it up (a big assumption -- I really don't remember my acoustics unit in physics very well) then this would require dogs to be able to hear sounds 21dB below the threshold of human hearing, or, roughly speaking (so to speak), sounds 100 times lower intensity than humans can hear. I don't know how well dogs can hear relative to humans but I would say that being able to hear 2 or 3 times better than humans would be impressive. Although they can definitely hear sounds higher than we can I have never had any reason to suspect that dogs can hear more than a bit better than we can in our overlapping range.
And of course, the difference between being able to detect a small difference under ideal conditions (what we mean by the threshold of hearing) and being able to reliably differentiate a complex sound from among a cacophony of similar and masking sounds is still apropos -- unless you are planning to conduct your tests in the middle of a deserted arctic ice-field when the air is still and the ice is stable.  |