catch 22. Those duct fans are pretty quiet compared to my 172 cfm inline vortex type fan. Closets are too big to be vented with computer fans, and they are just as loud anyways. There are no such things as silent fans, quiet...yes. But, silent....no. insulate the closet if you can, especially the door. if you have a computer, leave it on in there to help explain a fan noise.