In my opinion all the person needs is to see the sound, then it could be heard. It also depends on ur state of mind, if it constantly changes, like moving from one perspective to another day after day it could be done easly without any help from any person but coming from that person u see in ur own eyes.
There is a posibility to even hear the spoken word before it is spoken, or know the words of some song uve never heard just before it goes out of ur radio or such device, but it is extremly rare thing tto happen. U dont need any board or something that do as magical stuf, all u need is ur mind and the state ur in.