Delta BFB1212GH - Fan Noise

Datasheet: https://www.delta-fan.com/Download/Sp...

Its a Delta blower that produces 104 mmH2O of pressure, so of course it will be loud. Unfortunately, it's very annoying-sounding at low RPMs too. There is also some weird aerodynamic effects with this, it sometimes seems to lose a lot of its its pressure if there is enough impedance at the outlet, which doesn't line up with the PQ curve on the datasheet. Might just be my unit being a bit faulty.

Also oops its a bit out of focus in this video. Not like there's a lot to look at though with the blades being pretty enclosed on blowers. The blades are a bit forward-angled, so it is designed to move some volume of air and not just be a compressor.