Soundproofing inline fan box (will this overheat my fan?)

Hi..
I'm planning on making a soundproof box to house an inline fan in (elicent 150B)..

I was first thinking of making a really small box with foam walls that will basically leave the flanges (and only the flanges) exposed...which would make the thick egg foam (like egg mattress pad only a good thick one) be pressed up against the body of the elicent pretty tight in order to still leave the flanges exposed.. then I was thinking encasing it in an outer box with it hanging from bungies from all points so its orientation doesn't matter and run ducts from the flanges of the fan to flanges i'll mount on the outer box..

Right now I just thought of maybe hanging the fan inside a box from bungies (making the box as small as possible) and then putting that box in another box with like 4-6" thick of some kind of soundproofing material (any ideas?)

Does anyone think this is a good idea/it'll work?

If you have a solution you used that's working good and you don't mind posting it I'd really appreciate it and I'm sure RIU would like it too =)

it sounds like a great idea.. i have been trying to come up with something along the same lines as you.. although the activeair fan i purchased says in big old letters quiet operation, it is far from it.. its not really the fan that is that loud, just all of the air being drawn through it... i really haven't come up with anything better than the ideas you came up with.. i too was contemplating a box of some kind filled with some kind of soundproffing material too, but am at a stand still.. i went as far as buying some expandable foam from a hardware store, but that is about it.. i was thinking of maybe some packing peanuts or upolstery foam in a box, but haven't gotten around to attempting a build of anykind..
when and if you get this figured out, i would love to know some of the details of how you did it and your results if that is not asking too much..
best wishes on your quest for quietness.

im gonna make something like this soon but ill probably just head down to the goodwill and pickup some old bed comforters or sleeping bags to wrap my fan in. from what ive read the fan will cool itself so you can wrap that bitch as tight as you need to. insulated ducting is suppose to help considerably as well. and try and reduce your duct bends.

Get some sound absorbing insulation from home depot or building store, its a big bundle tho for such a small project = $
(unless you need to do your grow room walls too...)

So hows this look? (theoretically not aesthetically! )

I'm also thinking maybe just 4 bungies, put 2 on the top in the dead middle going one way (eg left & right) then 2 going the other way (front and back)

a good question would be if this soundproofing foam is flamable? it would be a disaster if it is , electrical parts next to flamable foam in a box. but none the less i have been thinking of trying this to