IBM IC25N020ATDA04 - Travelstar 20 GB Hard Drive - Discrete Tone Penalty

6.7.2 Discrete tone penalty
Discrete tone penalties are added to the A-weighted sound power (Lw) with the following formula only
when determining compliance:
Lwt(spec) = Lw + 0.1Pt + 0.3 < 4.0 (Bels)
where
Lw = A-weighted sound power level
Pt = Value of desecrate tone penalty = dLt – 6.0(dBA)
dLt = Tone-to-noise ratio taken in accordance with ISO 7779 at each octave band.
Travelstar 48GH, 30GN & 15GN hard disk drive specifications
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