Who makes the most quiet fans? and not too expensive?

Vortex 6" fan plugged into the "speedster" speed control set halfway...insulated silver jacket ducting with the noise reducing clamps.

The 4" and the 6" are exactly the same noise level all the way up with no speed control (very important to reduce noise) and the 6" has way more cfm (air movemment). Go with the 6".

Also Vortex are far quiter than Can Fans.

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