H wrote on 24/12/2016 22:43:
Has anyone come across a device that could cancel out the noise from servers, ie. the fan noise? I have a server rack near my office and would like to see if i can decrease the noise level. It would seem to me that the steady drone of the fans could be cancelled out to a large extent.
It's probably too late for you, but the best solution is to buy office-grade servers instead of datacentre-grade servers
HP and Dell (don't know othjer brands so well) have two kinds of servers: "dense" rack-only servers (tipically 1U or 2U if we are talking about single servers and not Apollo or VRTX or blade) and "office type" servers, 4U to 6U.
Let's put aside Apollo, VRTX, and other blade, they are out of scope.
Dnese servers are extremely noisy because they have a lot of small fans turning relatively at high speed. This kind of server cannot be converted to free standing "tower" form factor.
The other kind of server is sold both in "tower" and rack form factor; they are bigger the airflow is forced by bigger fans that can turn to a lower speed to exchange the heat.
If the noise is produced by the rack fans, use, as someone else suggested, variable speed fans regulated by a temperature sensor.
In essence, you can greatly lower the noise "by design", but if you already have the equipment it can be too late.