It all comes down to sex and species
The word ducks covers animals with wildly different voices. The classic quack — loud, carrying and unmistakable — belongs to the hens of the familiar farmyard breeds descended from the mallard. A drake of the very same breeds cannot quack at all: his voice is a quiet, raspy whisper that barely crosses a garden. And the Muscovy, a separate species often kept alongside other ducks, neither quacks nor calls — Muscovies communicate with soft hisses, tail-wagging and head-bobbing, and are as close to silent as poultry gets. So the honest answer to the noise question is another question: which ducks, and how many of them are female?
When quacking ducks are loud
A flock of laying hens quacks as a group activity. They greet their keeper at full volume, announce the morning, comment on anything novel that appears in the garden, and hold extended conversations at feeding time — and a flock is always louder than the sum of its birds, because one duck's quack sets off all the rest. The noise is cheerful rather than aggressive and it happens in daylight, but at close quarters it is persistent enough that neighbours across a small fence will hear every session. Six hens in a suburban garden are a real presence; two are usually a modest one.
The quiet keeper's options
If neighbours are close and ducks are the dream, design the flock for quiet from the start. Keep drakes only — handsome, calm birds that go about their day in near-silence — or choose Muscovies, whose quietness surprises everyone who meets them. Siting helps as well: the house and run placed away from the shared fence, with hedge or fence mass between the birds and next door's windows, and numbers kept small. Remember the honest trade-offs — drakes do not lay eggs, and Muscovies are strong fliers who need their wings managed and can roost in trees if not settled into a routine.
Neighbour factors beyond volume
Volume is not the only neighbour consideration with ducks. A badly drained pen turns muddy and smelly, and smell travels as surely as sound; deep bedding, good drainage and regular cleaning keep relations sweet. Ducks are also at their very loudest when something is wrong — a predator scare in the night will wake the whole street — so secure housing is a neighbour policy as much as a safety one. Managed well, a small, thoughtfully chosen flock is an easy animal to live next door to.
Local knowledge before you buy
Breed guides will tell you what a duck is supposed to sound like; local keepers can tell you what it actually sounds like over your fence, in your street, at six in the morning. KinsLe's Pet Services Directory connects you with trusted local poultry keepers and suppliers who know the quiet breeds and the quiet set-ups first-hand, so you can choose with your ears open.