A sound can be weakly or strongly present, but it can only be absent in one way.
'Strongly present' describes the sound; if there is no sound, I think you need to be describing people's reaction to the lack of sound, or the remaining scene.
In my example, the silence isn't strong, but it might be remarkable, or enveloping, or notable or surprising or unexpected or unbelievable or unbroken or all-encompassing.
Geoff had a strong presence; the group strongly felt his absence.
Company A put in a strong presence at the trade show, Company B was totally absent.