Silence itself is a sound that you can experience, it's hidden behind the chain of thoughts that go through our mind every second.
When the thinking mind is quiet and when you're deep in meditation, it's hard to describe what you hear, but it is the sound of silence.
From what I have experienced, silence sounds to me like a straight line, a white noise which isn't unpleasant but comforting.
Listening to it helps my mind settle down and become aware of the inner me.
Close your eyes and let go of all the thoughts and all that negative energy.