Noise Related Issues

First, it should be noted that one of the reasons this is the top question is due to many companies over the years (decades) marketing their products as quiet, silent, whisper... when in reality they were quiet like a 747!  This did a great disservice to not just companies like Cool Components but also to newer fan technologies and advancements.  Should people still be skeptical when companies claim silence, unfortunately the answer is a very resounding, YES!!!  It is just an educated guess that since most of these companies aren't really cooling companies, they are rack manufacturers and others who just don't give cooling and the fans they use proper attention, and thus, they base the fans they use more on what is more readily available and what is cheaper versus what is most appropriate.  Cool Components started with customized fans and continues to have their fans custom made to fit the precise application.

Not All Applications Require Silence!  Most likely if you are on this page you are concerned about noise but sometimes noise in not a concern and more airflow is necessary, CCI offers High Velocity fans which spin faster, move more air and thus, are louder and we gladly admit that because it is what they are designed for!  The point is not all applications require silence so this section is more dedicated to those that require silent products.  This includes most home systems as well as conference rooms, offices, lecterns... 

The question is very simple, is it loud or not, the answer may also be simple but understanding the why and how some fans are quiet and some are not can help differentiate between products that are and are not very quiet.

Airflow Noise.  The bottom line is there is no magic fan that can move lots of air and be silent.  The key is simply a proper balance between fan speed (rpm) and airflow (cfm).  The very simple fact is that the faster a fan spins, the more air it will move and the more noise it will make.  This noise is simply from the 'reaction' of air being aggressively displaced.  Now one consideration with this is there are differences and advancements with things like fan blade design and the bearings and motors which can help reduce noise but honestly, it's not significant but at the same time, even 1db here or there can mean the difference between some people hearing the fans or not.  The design of the fan can also change the pitch of the noise created and be the difference between annoying or just white noise.

So the key for this section is very simple, to be silent you need a balance but also consider that there are also other factors such as, a fan unit venting a cabinet in a home theater has a different threshold then say a fan installed in a rack in a closet.  This is the reason why CCI products focus on variable settings, either through controllers or simply setting the voltage on the power supply and thus fan speed.  In creating and facilitating that 'balance' with different applications, CCI deploys fans that are quiet yet effective at 5-7V or can be run more aggressively at 9-12V (should be noted that not all products can be run at 5V).  What most everyone else does is kick down the voltage and provide no option to run more aggressively thus not providing for a greater range of airflow for those situations when more aggressive airflow is desired.

Motor & Bearing Noise.  The biggest shortcoming of other products and thus advantage to CCI products is the bearing type.  Every other company uses ball bearing fans which ball bearing fans were a great advancement over sleeve bearings decades ago but it makes no sense that companies that serve tech sectors and systems are not keeping up with technology.  Today's more advanced bearing systems include technologies like magnetic and fluid bearings.  

CCI has always used magnetic bearing fans and the difference is that ball bearing fans from day 1 begin a linear progression of getting louder and louder.  Usually within the first year of can begin to hear the bearing noise (not annoying yet) and usually within a few years most people want to replace the fans due to the annoying noise.  Magnetic fans will stay quiet on day 1, year 5 and beyond.  The technology simply makes sense where a magnetic field is created to essentially 'float' the spindle and there is no contact so no wear.  Should also note that when it comes to noise, ball bearing, dual ball bearing, all the same no matter what the marketing people say.

One other problem with bearing and fan noise is it can usually be at an octave that is not only audible but can venture into that annoying frequency range.  For the fan motors, they are generally fairly comparable as long as it's a quality fan.  Most fans have brushless DC motors and capable of lasting a long time and this is the rating often see, usually between 50-70k hours which means nothing if the fan is crazy loud after 20-30k hours.

Vibration.  This is another source of annoying fan noise.  While the smaller fans, 60mm and smaller, usually do not create much if really any perceivable vibrations, the larger fans can create a chain reaction of vibrations which most likely will be very annoying to anyone in earshot of the unit.  CCI isolates vibrations is by using custom silicone fan isolation mounts which coincidentally, also makes reversing the airflow a breeze (pun intended).  The mounts provide for easily removing, reversing, and then re-fastening the fans.