Travelstar 5K160 (SATA) Hard Disk Drive Specification
6.6Acoustics
6.6.1Sound power level
The criteria of
Measurements are to be taken in accordance with ISO 7779. The mean of the sample of 40 drives is to be less than the typical value. Each drive is to be less than the maximum value. The drives are to meet this requirement in both board down orientations.
Typical (Bels) | Maximum (Bels) | |
|
|
|
160GB, 120GB models |
|
|
Idle | 2.5. | 2.7 |
|
|
|
Operating | 2.7 | 2.9 |
|
|
|
80GB, 60GB, 40GB models |
|
|
Idle | 2.2 | 2.4 |
|
|
|
Operating | 2.4 | 2.6 |
|
|
|
Table 22. Weighted sound power
The background power levels of the acoustic test chamber for each octave band are to be recorded.
Sound power tests are to be conducted with the drive supported by spacers so that the lower surface of the drive be located 25±3 mm above from the chamber floor. No sound absorbing material shall be used.
The acoustical characteristics of the disk drive are measured under the following conditions:
Mode definitions
Idle mode: Power on, disks spinning, track following, unit ready to receive and respond to control line commands.
Operating mode: Continuous random cylinder selection and seek operation of the actuator with a dwell time at each cylinder. The seek rate for the drive can be calculated as shown below.
Ns = 0.4/(Tt + T1)
where:
Ns = average seek rate in seeks/s
Tt = published seek time from one random track to another without including rotational latency
T1= equivalent time in seconds for the drive to rotate by half a revolution
6.6.2Discrete tone penalty
Discrete tone penalties are added to the
Lwt(spec) = Lw = 0.1Pt + 0.3 < 4.0 (Bels)
where
Lw =
Pt = Value of desecrate tone penalty = dLt – 6.0(dBA)
dLt =
36/167
