Marpac Dohm Classic - Original White Noise Machine Like new. The sleep-inducing magic of a Marpac sound machine makes falling asleep as easy as pushing a button. Dohm Classic is the original sound machine, first invented by Marpac in 1962 and beloved by generations since. The Classic features Marpac's signature fan-based natural white noise, with two speed options for widely adjustable tone and volume. Just flip the switch to high or low, rotate the cap and collar to find the best sound for you, then let the noise-masking magic happen. Give sleep a chance! Masks background noises, for a better night's sleep Fan-based white noise is natural and soothing Two speeds for widely adjustable tone and volume.