Seagate Exos 7E8 SATA Product Manual, Rev. F
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b. Random Rotary Operating Vibration
The drive will exhibit greater than 90% throughput for sequential and random write operations while subjected to the shaped
random power spectral density noise specified below.
c. Linear Random Non-Operating Vibration
The drive will not incur physical damage or have non-recoverable errors after being subjected to the power spectral density noise
specified below.
2.8
Acoustics
Drive acoustics are measured as overall A-weighted acoustic sound power levels (no pure tones). All measurements are consistent
with ISO document 7779. Sound power measurements are taken under essentially free-field conditions over a reflecting plane. For all
tests, the drive is oriented with the cover facing upward.
)
*During periods of drive idle, some offline activity may occur according to the S.M.A.R.T. specification, which may increase acoustic and power to operational levels
.
2.9
Test for Prominent Discrete Tones (PDTs)
Seagate follows the ECMA-74 standards for measurement and identification of PDTs. An exception to this process is the use of the
absolute threshold of hearing. Seagate uses this threshold curve (originated in ISO 389-7) to discern tone audibility and to compensate
for the inaudible components of sound prior to computation of tone ratios according to Annex D of the ECMA-74 standards.
Note
For seek mode tests, the drive is placed in seek mode only.
The number of seeks per second is defined by the following equation:
(Number of seeks per second = 0.4 / (average l average access time
Table 6
Fluid Dynamic Bearing (FDB) motor acoustics
Idle*
Performance seek
All models
2.8 bels (typ)
3.0 bels (max)
3.2 bels (typ)
3.4 bels (max)
