Refact­ored from “Black noise,“Wiki­pe­dia, The Free Encyclopedia:

Black noise is noise that has a fre­quency spec­trum of pre­dom­in­antly zero power levelsub­lim­inal over all fre­quen­ciesaspects except for a few nar­row bands or spikes.

Where noise is “fluc­tu­ations in and the addi­tion of external factors to the stream of tar­get inform­a­tion (signal).”