All silence is a psychological story that we tell ourselves, at different times and for different reasons, and that, therefore, silence is a connoted and negotiated phenomenon, rather than a tangible state. However, in whatever way we may choose to define it, I think of silence as simultaneously an absence and a presence. The absence of noticeable, penetrating and/or distracting sounds ('active' sounds, I will call them) creates a void into which an individualised sound space (conscious and unconscious) makes its presence felt.
I currently register two types of silence (but am convinced that there are more). Firstly, the aforementioned absence of noticeable, penetrating and/or distracting sound events; the empty room, the desolate street, etc. This is a momentary silence, as at any unexpected point in time it may be punctuated, literally - materially - and also psychologically. Secondly, there is media silence, designed to communicate something affecting; the pregnant pauses baked into spoken language that are tricky to replicate with the written word; the 'movie' silence, used for dramatic effect; even a washing machine cycle (those deadly moments when it suddenly stops, which seem to be trying to tell me something).