man hdparm
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-E
Set cdrom speed. This is NOT necessary for regular operation,
as the drive will automatically switch speeds on its own. But
if you want to play with it, just supply a speed number after
the option, usually a number like 2 or 4.
####
-M
Get/set Automatic Acoustic Management (AAM) setting. Most
modern harddisk drives have the ability to speed down the
head movements to reduce their noise output. The possible
values are between 0 and 254. 128 is the most quiet (and
therefore slowest) setting and 254 the fastest (and loudest).
Some drives have only two levels (quiet / fast), while others
may have different levels between 128 and 254. At the
moment, most drives only support 3 options, off, quiet, and
fast. These have been assigned the values 0, 128, and 254
at present, respectively, but integer space has been
incorporated for future expansion, should this change.
####