i'm thinking a 600watt hps , i'm getting a 6" fan for exhaust and passive intake , and either a cool tube or vented hood/reflector.

I also was thinking, would it work if i put my fans in a cardboard box, put maybe insulation or something in side the box with the fan, put cover on it and sealit up and cut duct holes in the top and bottom, would this mufflle fan noise?
any input would be appreciated