I have a small hard drive that is making a constant high pitched sound that is typical of the drive, and not very noticeable to the average person, but I have pain induced noise sensitivity. I am curious about how to calculate damping potential. As an initial guestimate, the frequency is very near to my maximum audible range and likely around 12kHz-16kHz. It is a little higher than the switch mode power supplies that I can also hear if it is dead silent in the room, although the drive is a higher amplitude. Addressing the noise with a solution is probably beyond the scope of anything I would actually do, but knowing how to solve it is far more interesting to me. (ELI15 )
That’s not entirely true, cancelling sound waves can also be done on a large scale. I’ve seen it on festivals or other open air venues, where they stack two rows of subwoofers behind each other in a precisely calculated distance to cancel out the bass notes towards the back of the stage, meaning walking in front of the subs you could hear it normally, walking behind them and the bass notes where very faint and clearly coming as a bounce back from walls or the like. So they effectively cancelled out the frequencies towards the back.
But that doesn’t help OP since that works way better on lower frequencies, with higher notes you’ll need the precise localization you’re talking about. So the high pitched noises from a hard drive probably won’t work.