Noctua NF-F12 Push/Pull loud for some reason, suggestions welcome!

[Izay]

So I'm gonna get right to the point.

I've got a HAF12 case (not the quietest case in the world I'll grant you) and my Push/pull setup for my H60 is loud. It's set as intake from the rear exhaust. Normally I would just be "huh, I guess the fans aren't that quiet after all", but I've got another NF-F12 as top Exhaust and it's dead quiet even at 12V.

If I hold my hand over the mesh at the back the sound seems to go away somewhat, so I'm wondering if the noise (It's like a loud buzzing noise) comes from the air going through the mesh? or can it be because of the air hitting the fins of the "rad"?

I'm half tempted to switch the fans around to see if the different direction of air flow will help decrease the sound or just cut away the mesh all together and slap a dust filter on there. Suggestions?

 

[Josh Weston]

The H60 has a high FPI count, which gives a lot of resistance. I'd hazard a guess that it's that which is causing the noise.
P.S. - your NF-F12s are silent at 12v? I'm jealous.

 

[airdeano]

some complaints of the single 120 rads mounted to the the exhaust outlet about
a buzz, chop, or loose humm. some isolators have cured the problem. but some
believe it is the mesh. if the panel is flat, theyve gone so far to mount the fan to
exterior, panel, radiator, 2nd fan (optional). and still some have the issue.
the f12 (having isolator corners) could calm the issue, but again, there is so
many other things it could be as well. but try that idea and retest..

airdeano