We've found 2 quotes for 'audio frequency'(0.1 seconds):
"Machines take me by surprise with great frequency." »Alan Turing
"For a smart material to be able to send out a more complex signal it needs to be nonlinear. If you hit a tuning fork twice as hard it will ring twice as loud but still at the same frequency. That's a linear response. If you hit a person twice as hard they're unlikely just to shout twice as loud. That property lets you learn more about the person than the tuning fork." »Neil Gershenfeld
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