With SSDs increasingly serving our high-performance storage needs, the acoustic footprint of hard drives has arguably become a more important differentiating factor—especially for PC enthusiasts who have built themselves near-silent systems. We're a little OCD here at TR, so we've constructed a Box 'o Silence to test the noise emitted by mechanical hard drives. This 18" x 20" anechoic chamber is lined with acoustic foam, and we suspend hard drives inside it, exactly 4" away from the tip of our TES-52 digital sound level meter. You can read more about the setup here.
To ensure the lowest possible ambient noise levels, we swapped the test system's graphics card for a passively cooled Gigabyte model and unplugged one of the Frio CPU cooler's dual fans. Noise levels were measured after one minute of idling at the Windows desktop and during an HD Tune seek test.
We've color-coded the results by manufacturer to make the graphs easier to read, marking the Desktop HDD.15 4TB with a darker shade of green than the other Seagate drive. Because they have no moving parts and are essentially silent, the SSDs are missing from the noise results. When they do appear in the graphs, the corresponding bars are greyed out to set apart what is really a different class of PC storage.
The Desktop HDD.15 is a little quieter than its 7,200-RPM sibling at idle, but the two make about the same amount of noise when seeking. Seagate's acoustic specifications put the two drives on relatively equal footing, and our results agree. Any acoustic advantage imparted by the HDD.15's slower spindle speed is likely nixed by the addition of the fourth platter. We've found four-platter drives to be generally louder than their three-platter counterparts.
That said, the Desktop HDD.15 is still a very quiet drive. It registers a couple decibels below the WD Black 4TB at idle and nearly seven decibels lower while seeking. The HDD.15's seek chatter sounds muffled, especially when compared to that of the Black. Clearly, though, the WD Red is our low-noise leader. The thing barely makes a whisper regardless of whether it's idling or seeking.
We should note that, even when idling at the Windows desktop, the Desktop HDD.15 vibrates enough to make the suspension cords in our test chamber oscillate with a slight hum. When this happens, the drive starts chirping audibly—perhaps an artifact of AccuSync adjusting for the vibration. Putting a paperback book on top of the drive adds enough weight to tension the cords, dampen the vibration, and eliminate the chirping. Apart from cutting out vibration-induced noise, the book's presence doesn't appear to change the HDD.15's decibel output. We tested the WD Black 4TB with and without the book and found no difference in the readings on our meter.
Power consumption was tested under load with IOMeter's workstation access pattern chewing through 32 concurrent I/O requests. Idle power consumption was probed one minute after processing Windows 7's idle tasks on an empty desktop.
Thanks in part to its lower spindle speed, the Desktop HDD.15 consumes relatively little power. Under load, it draws less than half of the wattage pulled by the Black 4TB. The WD Red does consume fewer watts than the HDD.15, but it's a terabyte behind on the storage front.