What is an antonym for noisy?

Here are some antonyms for "noisy", depending on the context:

General:

* Quiet

* Silent

* Peaceful

* Still

* Hushed

* Serene

Specific:

* Calm (for a person or situation)

* Tranquil (for a place)

* Muffled (for a sound)

* Soundproof (for a room)

* Subdued (for an event)

* Discrete (for a sound or activity)

The best antonym will depend on the specific meaning you want to convey.