Noizio is an app that will drown out the noise of the street and allow you to concentrate on the work at hand, increasing your productivity. On the other hand, it can also set the mood for a romantic evening or lull you to sleep, ensuring that you will dream soundly all night long. An ambient sound equalizer app for creating a mixture of ambient sounds available for macOS.
Headspace - Meditation made simple. Brilliant things happen in calm minds.
Noisli - Noisli is a fantastic background noise and color generator for working and relaxing. Online soothing ambient sounds like White noise, Rain and Coffee Shop.
Calm - Calm.com can help you reduce stress and increase calm.
MyNoise - Custom shaped online noise machines. Many Many generic sounds
Mezmind - Calming Interactive Environments
A Soft Murmur - Ambient sounds to wash away distraction.