Quote Originally Posted by WashougalWonder
Well consider this, the fiberglas is added friction so it will reduce the total volume. Not only that, those fibers will break and be blown to whatever is at the end of the duct and if a filter will eventually plug it up.

My noise comes from the fan itself and by putting the CF on the exit side I got 75% noise reduction and on the intake side only 50%. The exit side is the part I want quieter.

GAGrown, not trying to hijack the thread here.....will do my own when I get this going.
Your GOOD,Brutha!:thumbsup: That's info, people need to know! Let me share this with ya,about fans. They work on the same principle as, "It's easier to push than it is to pull." Objects that is... Air is just the opposite. The reason your noise was reduced.. Was because your using only half of your intended CFM.. Because your building up static pressure in your can filter.It backs up and turns to negative pressure resulting in cfm loss and compromises the intentended use of the filter. I love ventilation issues as well.:thumbsup: