It's inevitable: unless you book a very private room somewhere, the sounds of the city will intrude somewhat on your wedding ("the rumble of the subway train, the rattle of the taxis" - the lullabies of broadway, of course). If you enjoy the ambient noise of the city, it's just part of effect. But just remember that you are outside in a city of millions of people - not sealed away in a chapel or hotel room.
Central Park on a Saturday evening is usually LOUD. Concerts, impromptu musicians, amplified music at Wollman Rink, inline skaters with boom boxes by the Mall, the guy who busks by the Ladies Pavilion with the endless John Denver songs, the Tango dancers, SummerStage, and last night, a really loud concert in the Bandshell, which could be heard all the way to Strawberry Fields (where there was the usual Saturday evening jam). And I was at a wedding at the Boathouse with a 12 piece band that rocked the lake. So if you want a quiet wedding in the park, go north, go waaay east, or don't get married Saturday night in the summer in the usual places unless you're prepared for the city at play soundscape. Though, of course, you can find nice quiet spots at any time -- just be prepared to walk a bit further away..
Grand Central is noisy. Battery Park is noisy. Water taxis disturb weddings at the Brooklyn bridge parks and at Fulton landing, and Red Hook. The subways crossing over in DUMBO (DOWN UNDER MANHATTAN BRIDGE OVERPASS)are going to interrupt your wedding every 6 minutes.
Remember that planes change their flight plans at dusk - and often fly over the lake and ponds. We had a wedding on Gapstow Bridge interrupted by a big gas lawnmower on Saturday. School and tour groups suddenly appear anywhere - squealing loudly - at Strawberry Fields, the Top of the Rock (we married a couple there on Wed. and had to wait till 120 kids decided to go to another level), and of course Times Square is what it is -- at least they aren't yelling outside the MTV window these days. Always check park events - even Fort Tryon Park gets festivals and events. But it might be fun to get married during the Renaissance Festival!
UPDATE 2020! Mary has relocated to Toronto, Canada. You can find information about Canadian weddings at ElopeToronto.com I'm keeping this blog because I've been told it's very helpful for couples in New York! If you need a wedding officiant in New York or Toronto, email me at MaryBeaty (at) gmail (dot) com, and I'll try to help. Best wishes! Stay safe!