silence is unknown in NYC.

but early in the morning after a heavy snow fall, there is something close to it.. the snow dampens distant sounds-- every neighborhood a highway or major thru street within a few blocks--so traffic is always there as constant--but snow reduces traffic, and dampens the sound of what is left.

and small close sounds, like footfalls go away too.

but we city dwellers do not 'close our ears'or miss small sounds just because of a constant background of noise--a quick fun experiment can be done with $3 to 4 --drop a penny, (on a busy street) and most will ignore the sound.. but drop a US quarter on concrete--not a very big sound, but passers by will hear it, and look for the quarter..

(this experiment was done by a scientist from Mus. of Natural History--and reported about..a naturalist heard a cricket on columbus avenue-- (and pointed out that no one else seems to here it..) but his companion, a anthropologist, pointed out, in NYC a cricket wasn't an important noise.. and the clink of quarter on concrete was.. and NYer would hear that small noise (over the noise of cars, and buses, distant sirens, footfall, boomboxes..etc) and he was right.

silence isn't natural.-not is cities or elsewhere..
but close listening can be practiced. (i have made a point at times to listen for crickets..--and have heard them and i have found beautiful little mushrooms (growning in planters, with evergreens, outside trump tower on 5th avenue)
and last weeks the NY times had a wonderful article about practicing listening to others coversations when in public..(close your eyes and feign indifference.. but take in every word.. its a fun hobby!)