Noise Level Results
At near 1200RPM I was only able to hear the fan if I were within a foot of it on the open air test bench. Since I test one foot away from the coolers it was within range and I was able to get the reading of 31 dB at this speed.
With 12V going through the fans, and reading a speed of 1805 RPM, the reading on the meter was bottoming out at 52 dB. While not the quietest fan we have tested, it plays right into the averages of what I have tested in this manner.