G.W.

I know this has been answered but I'll do some informative post whoring anyway.

wall wart
Google

if you find the noise too much try dropping the voltage
most 12v fans will start at 7v or higher.
I have some 6" Noctua that literally cannot be heard 5 feet away @10.5v.

here is a writeup with brands and voltages
SPCR • View topic - The Top SPCR Quiet 120mm Axial Fans Compared + 120mmAC Fans.

Look for fans with speed adapters included.

Bearing type is also a noise and service life determinate.
Ball bearing offer longest life and often jet engine sound with increased price.
Sleeve bearings are cheaper and quieter but have a shorter service life and will benefit form oiling peridiocally.
Bearing type determines mounting, eg vertical mounting is only recommended with ball, all others horizontal (shaft) only.
Other types exist which may claim vertical mounting but with mixed results.

I think I've wasted enough space here.....

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winter winners, jackfruit, carambola, hua moa, d namwah, hak ip lychee with pink leaves 2 days before a cold snap eeeek!

Winter losers, kohala longan, misi luki, 80% jackfruit seedling loss

first bloomers, HUA MOA, DC, D NAMWAH, FHIA 17, KANADARIAN, RAJA PURI, M D NAMWAH

best bunch FHIA 17 , undisclosed

WORST BUNCH hua moa, 2 fingers