For those of you who switched from a Drobo-v2 to a Drobo-S, did you notice any +/- noise change ?
I am considering moving from a Drobo-V2 with 4 WD 2TB AV-GP GreenPower (WD20EVDS) to a Drobo-S with dual disks redondancy and 5 WD 2TB AV-GP GreenPower.
Obviously, increasing the number of disks will increase their noise and the power consumption, thus the fan noise, but I would like to be sure it is not even worse for some other reason.
As many people on this forum who use Drobo direct attached for home theater purpose, I find the Drobo noise somewhat invasive when video sound level is low.
My Drobo S is quieter than my Drobo v1 by a factor of 6,525,234!
I never had a v2.
most jet engines are quieter than drobo v1
According to the Technical Specs :
Drobo-V2 : Normal operation: 20.9dB (negligible) to 24.2 dB
Drobo-S : Normal operation: 31.8 dB
So that would make the idle Drobo-S MUCH NOISIER than Drobo-V2 (11dB, ie. about 8 times more).
This is somewhat consistent with the idle power consumption :
Drobo-V2 : Idle system (standby, drives off) = 5 watts
Drobo-S : Idle system (standby, drives off) = 12 watts
This definitely does not go into the right direction, especially when “green drives” (such as WD WD20EARS) have a Standby consumption of only 0.80 Watts (= 3.2W with 4 drives).
Why is not Data Robotics able to build electronics with a much lower idle consumption ? If they need 12 Watts only to monitor 5 temperature censors and FW/USB reconnections, there is something very wrong there…
Drobo S has a faster processor, perhaps even a different architecture. The price for performance is increased heat. 
I may agree with that when the Drobo is running.
But when it is sleeping, it is just sloopy enginering, especially considering the price increase (+100% !!) between Drobo-V2 and Drobo-S.
Data Robotics did improve the noise level from Drobo-V1 -> V2, it is extremely disappointing they destroyed part of that gain with Drobo-S.
Well, considering the noise issues raised in this other thread, my question seems now to be answered : the Drobo-S fan is MUCH louder than the Drobo-V2 one, especially when the Drobo is idle.
This is consistent with the +11db shown by the respective technical specifications.
One year later, we have likely had many more migrations from Drobo V2 to Drobo-S.
Have those who did it experienced the large noise increase experienced by the first migrants and supported by the specs (+11db) ?
How many of satisfied Drobo-S users use it in a living room or a bedroom without any noise disturbance when the Drobo-S is idle ?