Re:Western Digital is trying to redefine the word “RPM”
by floatingatoll on Tuesday September 08, 2020 @02:28AM
(#24405718)
These are definitely the right questions to be asking about the sounds of hard drives, regardless of their RPM. My most important question is subjective: “are they essentially silent from a few feet away”, which is often simple to answer given a drive to test — but difficult to learn from specs and frequency charts alone.
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Re:Western Digital is trying to redefine the word “RPM”
by acqq on Wednesday September 09, 2020 @02:40PM
(#24424245)
> regardless of their RPM.
It's not regardless:
5400RPM == 90Hz
7200RPM == 120Hz
The human perception curve shows that the humans hear much better the sounds at 120Hz than at 90Hz,
https://en.wikipedia.org/wiki/Equal-loudness_contour
That means that for the same reported noise level of e.g. 30dB a 5400RPM drive is much more quiet for humans than a 7200RPM drive.
That is how the people recognized that these HDs aren't 5400RPM -- they sounded "too loud" so they took the sample of the noise and drawing the histogram they proved that the peak was at 120Hz.
As far as I know, nobody managed to produce a 7200RPM drive which does not have a peak at 120Hz. If you know some that doesn't have such characteristic, please write, everybody will celebrate that achievement.