USER RESPONSIBLE FOR VERIFYING VERSION AND COMPLETENESS
OEM FUNCTIONAL SPECIFICATION ULTRASTAR XP (DFHC) SSA MODELS 1.12/2.25 GB -1.0" HIGH
7.4 Acoustic LevelsAdditionally, the population average of the sound pressure measured one meter above the center of the drive
in idle mod e will not exceed 36 d B.
Additionally, the population average of the sound pressure measured one meter above the center of the drive
in idle mod e will not exceed 41 dBA.
Notes:
1. Th e above octave band and maximum sound power levels are statistical upper limits of the sound
power levels. See C-B 1-1710-027 a nd C-S 1-1710-006 for further explanation.
2. T he drive's are tested after a minimum of 20 minutes warm-up in idle mode.
3. T he operating mode is simulated by seeking at a rate between 28 and 32 seeks per second.
4. The mean of a sample size of 10 or greater will be less than or equal to the stated mean with
95% confidence.
Upper Limit Sound Power Requirements (Bels) for C1x & C2x Models
Octave Band Center Frequency (Hz) A-weighted (see notes)
125 250 500 1K 2K 4K 8K Maximum Mean
Idle 4.5 3.5 3.3 3.5 4.5 4.5 4.5 5.00 4.7
Operating 4.5 4.0 3.6 4.1 4.8 4.8 4.5 5.25 5.0
Upper Limit Sound Power Requirements (Bels) for C4x Models
Octave Band Center Frequency (Hz) A-weighted (see notes)
125 250 500 1K 2K 4K 8K Maximum Mean
Idle 4.6 3.5 3.3 3.5 4.5 4.8 4.8 5.0 4.7
Operating 4.6 4.0 3.6 4.1 5.1 4.8 4.8 5.3 5.0
Source filename=OPLIMITS IBM Corporation Page 83 of 87