White Noise (more accurately known as "sound masking") is based on the phenomenon that when "low level background noise" is added to an environment, intruding speech and noises are less intelligible. The term "white noise" is widely used when referring to speech privacy or sound masking systems, although these systems don't actually use white noise.ound masking "fills in" the sound spectrum around you with barely perceptible "low level noise", so that speech is rendered unintelligible.