So yesterday at BE, we were doing this thing to show our appreciation to the teams that make us breakfast every Saturday and met in a different room than usual. This meant that we had to set up with different sound equipment than we were used to. As we ate, the system was used for some background music, but then the playlist ran out and the board started acting up. It started to send a high pitched sound out through the speakers. Obviously, this sound was quite annoying, and I began to wonder why exactly my dad (who normally runs the sound system) wasn't doing anything to fix it. My sister was visiting from college, so she went up and asked him if he was going to do anything about the sound, to which he replied, "what sound?" This noise was at such a high frequency that my dad couldn't hear it, and thus didn't know anything was wrong. A young, healthy human can hear sounds from 20 Hz to 20,00 Hz. This range deteriorates the older a person gets, explaining my dad's sudden lack of desire to fix the sound. He didn't hear anything wrong, so he did't go to fix it meaning that I had to go try and figure out what was wrong. I couldn't, so i just shut it off.