Another change for silence.

[Destil]

I always liked sound bubble better than silence. It creates a bubble through which sound can not pass in either direction. People within the bubble can hear everything within the bubble normally and same outside, but nothing passes through. This plus a spell that prevents a single creature from producing any sound and we'd be set.

I also have to say that anyone would be set on edge, whether consciously or not, by a zone of silence passing near them. The sound of water would become intermittant, sounds from the market would be dulled, animals would suddenly quiet, creeking would stop. True silence is totally unnatural and I would grant anyone "hearing" it and listen check to notice it. It would be different if it were a targeted 1 person spell, but this is an area.

YMMV
DC

I have a custom spell that works like this: airless barrier, which creates a thin hemisphere shell of vacume that hedges out gassess and stops sound. More often than not I've used it to sleep through noisy party debates my semi-apetatic mage dosn't care about, though.