How does the sound of the Uno compare to the Dohm Classic? May 12, 2020 15:43 The single speed Uno has a sound comparable to that between the high and low setting of the Dohm Classic. Related articles What is the energy usage for the sound machines? Does the Purest Sleep Diffuser have a white noise option? What is difference between the Dohm Classic and Dohm Natural? Which sound machine is best for me? What is “pink noise”?