Poorman's enclosure 36 decibel reduction

I wanted a window in the door. I was advised by my esteemed college to have a solid door since I have a camera inside. I listened and learned and SUCCEEDED ! Using a decibel meter I measured the noise of the makita inside the closed box at 94 decibels then I measured the makita from outside the box and it was 58 decibels. It looks okay and does the job. I did beef up the interior with my cheap version of mlv (rubber matting - aluminum flashing - rubber matting) and than a layer of ceiling tiles. That increased the noise reduction by 14 decibels over my last post in the “enclosure zoo”. Thanks to Mark Bellon’s advise and encouragement. The kirby vacuum cleaner is another issue, I’ll just build a small impeller blower along with the small cyclone and replace it. That noise is too loud even with reduction.


Update on my enclosure: I redid the vacuum cleaner compartment using what I had available. Couch foam cut 2 inches thick for the baffle inside the air intake, my version of MLV (aluminum flashing with rubber tape both sides) and 6 inches couch foam on top for the fun of it. Decibel reading for the vacuum now is 80 decibels down from 101 decibels. Only 21 reduction but it is at least endurable and didn’t cost me any extra money. I’ll still build an impeller blower and a cyclone separator because I have extra motors and a piece of 6" diameter aluminum pipe (for the impeller blades) later on when time allows. Than I’ll heed Mark’s advice and build an actual sound reducing enclosure without the couch foam. Couch foam is better than egg cartons but couch foam and MLV is 21 decibels better than egg cartons, or maybe the MLV is 20 decibels better than egg cartons. Anyways, using my methods only work when you can’t afford the real materials and if you want real sound reduction than paying attention to Mark’s comments is the way to go.