Dr. GURU speaks,
A 'sound' is the perception and interpretation of a sound-wave. A falling tree always produces a sound-wave through the atmosphere, but there may be no-one to hear it, and so there is NO noise unless you are there.
Recording a tree falling when you are not there only achieves in designating the necessary tasks of reception, analysis and storage of the sound-wave to the recording equipment.
The ill-fated Existentialist might apply a similar question to the sense of sight, e.g. "Does an object exist if no-one is there to see it?". The equal of sound, is sight; but not in their literary meaning. A sound-wave can exist without a sound, but the visible light-wave cannot exist without the subject that it bounces off-of.
Material things are there despite us. They were there before we were born, and they will be there long after we die. The Spiritual, on-the-other-hand, the perception and interpretation of the world around us, is the Reserve left only to us.
The GURU must now sleep.