I mostly meant it as a reply to the guy trying to figure out how to make them quieter in a home environment. Mod the case and use bigger fans.
Bigger fans have nothing to do with it. I believe it was confirmed that the psu is what makes them so noisy.
The PSU has one or more small fans as well, though it does sound like that might eventually get quieter with a firmware fix.
Small fans have to spin faster to move air and are therefore almost always much noisier than bigger fans given the same cooling requirement. 1250 watts in 1.25 U is a lot. Cooling that with 40 mm fans will likely always be at least somewhat noisy.