Seagate ST340015ACE manual Acoustics, Acoustic mode, Fluid Dynamic Bearing FDB motor acoustics

16 Barracuda 5400.1 Product Manual, Rev. G

2.11Acoustics

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.

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 latency + average access time)

Table 1: Fluid Dynamic Bearing (FDB) motor acoustics

		Acoustic mode
Model	Idle*	Quiet seek	Performance seek
ST340015ACE	2.6 bels (typ)	2.7 bels (typ)	2.8 bels (typ)
	2.8 bels (max)	2.9 bels (max)	3.0 bels (max)

*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.