Developed almost 50 years ago, this is the Original sound machine you've probably heard about. Its dome shape is easy to recognize. Turn it on, and tune out the rest of the world. A single speed - high - provides plenty of sound-masking power. Dohm creates the soothing sound of rushing air, also known as "white noise," which has been proven to effectively block noises at a broad range of frequencies, so a uniform blanket of smooth sound masks disruptive noises. The tone and volume alterations are just a twist away. It's a personal sound environment that you control.