It depends on what you call loud, but the best way to quiet it is return it to who you bought it from. If you are on a budget like I am, I found decent 6" fans on ebay, they are Tjerlund fans. Do a search for 6" inline fan and you can usually find them as a buy it now for $84-$95 plus shipping. These fans are very quiet compared to other fans I've heard running. They run smoothly and as far as the sound goes, it sounds similar to air coming out of your a/c vents. No shit!! I havent had them running more than a few hours yet, but so far so good. Hope this helps. Here's a prime example of how quiet they are. I bought a Delta computer fan that moves 300+ cfm's and it's easily 3x's louder than the fan from ebay. And lastly, you may want one of these anyway, you could get a speed controller, to slow the fan down some. I found them on Amazon.
