@Dr. Nagler draws a useful comparison between the heightened acuity of our vision in a dark environment (pupil dilation etc.) and our heightened sensitivity to sound in a silent environment.
That makes sense but I notice something else. A silent environment initially brings T into the foreground. There is nothing else to focus upon so we focus on the sound of our T and it seems ultra-loud. But after lying in bed for a while listening to T while trying to get to sleep, I usually find something strange happening. The central T tone will begin to reduce in intensity. When it recedes, a metallic hiss becomes the dominant sound. This hissing is less bothersome than the high-pitched pure tone. Anyhow, I usually fall asleep pretty soon after that point. I guess this means that my T must have a reactive component. So it seems that the analogy between sight and vision (and how they react to lack of stimulus) is only valid up to a point or is not valid in every case. T is a complex phenomenon as we all know.The net result is that in a silent room, your tinnitus is greatly magnified.