The divine revelation at Mount Sinai was in some way more direct than a regular sensory experience, whereby one merely sees the visible and hears the audible.
It was a revelatory experience untainted by even the slightest shade of concealment, a sensation of such a pristine
caliber that the people saw the audible and heard the visible.
It was an unfiltered, tangible experience of the divine essence that breached the normal boundaries of the senses.
The divine speech heard at Mount Sinai was not experienced as emanating from a single direction.
No matter the direction a person faced, he could hear God’s voice originating from that point.
It did not come specifically from Mount Sinai, nor from any hidden locus; it issued forth with equal intensity from the four directions, from above and below, from within and from without.
It was a direct revelation shattering the boundaries of space, transcending both the normal parameters of human perception and sensation, rendering meaningless even time and space.
Rabbi Adin Steinsaltz