We take the issue of noise very seriously at KitGuru and this is why we have built a special home brew system as a reference point when we test noise levels of various components.
Why do this? Well this means we can eliminate secondary noise pollution in the test room and concentrate on components we are testing. It also brings us slightly closer to industry standards, such as DIN 45635.
As this can be a little confusing for people, here are various dBa ratings in with real world situations to help describe the various levels.
KitGuru noise guide
10dBA - Normal Breathing/Rustling Leaves
20-25dBA – Whisper
30dBA - High Quality Computer fan
40dBA - A Bubbling Brook, or a Refridgerator
50dBA - Normal Conversation
60dBA - Laughter
70dBA - Vacuum Cleaner or Hairdryer
80dBA - City Traffic or a Garbage Disposal
90dBA - Motorcycle or Lawnmower
100dBA - MP3 player at maximum output
110dBA - Orchestra
120dBA - Front row rock concert/Jet Engine
130dBA - Threshold of Pain
140dBA - Military Jet takeoff/Gunshot (close range)
160dBA - Instant Perforation of eardrum
Noise was measured from half a meter away with two 6TB drives installed.
The system is generally, just audible. when loaded with sustained activity across all drives, the fans spin up to compensate for rising temperatures, peaking at around 35 dBa, clearly audible, but perfectly acceptable within a business environment.
The power drain was around 78 watts when loaded, and this drops to around 47 watts when idle. Populating the unit with more drives will obviously raise the overall power demand.
Time to test the cooling system. Our room ambient temperatures are 23c which is a reasonable temperature for most people to work and relax within.
Thanks to the clever use of two high quality 120mm fans, the DS3611xs receives a constantly high air flow from front to back. Temperatures idle around the 28c/29c mark, rising to 33/34c under extended load.