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 )
Absorption coefficient depends on material.
In your case, literally any enclosure at all will make a big difference. If you want to truly eliminate it, the most effective way would be to replace the drive.
But is there a direct rule of thumb (or more) about the relationship between density, thickness, and frequency?