Best sound-proofing material?

[sub]

Hey guys, so I was just thinking about ways to lower the noise of my cab. The exhaust fan will be on top of the box on the outside. I had planned on encasing it in a cardboard box and filling it or wrapping some kind of material around the exhaust fan to reduce noise. It's a pretty damn quiet fan to begin with, but I'd like to make this as stealthy as possible.

Will filling the box up with packing peanuts do a good job or is there something better I can use? I do have thick insulated ducting as well which helps with noise.

I've also been considering some kind of sound-proofing material that is not combustible to line the inside of my cab, behind the panda film.

Anything like that? Maybe just any kind of foam? Anything specific?

I will be using LEDs so heat isn't a huge issue, but better safe than sorry, right?

Thanks guys!

 

[thatonedude]

or just don't let anyone the room with the cab. foam sounds good though

 

[sub]

Well that's not really an issue, it's more for the "just in case" category, and just for my own OCD-ness I just love the idea of stealth, even if it's not needed

 

[thatonedude]

well. the packing peanuts sound good. if that don't quiet things down enough for you you could always buy som actual soundproffong material. I assume your fan is already isolated(ie not touching anything, suspended)

 

[BrnCow]

Boxing the fan might catch the fan/room on fire. Fan speed control might help...insulated box 6" bigger on all sides than fan with some form of vent fan might work...might build an open top box out of insulation or foam board.

 

[sub]

Boxing the fan might catch the fan/room on fire. Fan speed control might help...insulated box 6" bigger on all sides than fan with some form of vent fan might work...might build an open top box out of insulation or foam board.

Oh yeah I didn't mean the fan would be in a full closed box, one side will be open with a screen on it to hold the material inside

 

[sub]

Either a screen or another hole at the opposite end where the ducting can vent through, so it's literally just sound-proofing around the fan/ducting, no impeded airflow

 

[ceosam]

Boxing the fan might catch the fan/room on fire. Fan speed control might help...insulated box 6" bigger on all sides than fan with some form of vent fan might work...might build an open top box out of insulation or foam board.

That was my first thought, then I thought because the fan is moving air it is cooling itself so it won't overheat.. ?

 

[sub]

Just picture ducting connected to a fan on both ends. The box would encase the fan with the ducting running through the entire box - if that makes sense.

Like this:

====ducting=====[[box+fan]]====ducting=====

 

[sub]

OOOH, actually I might have access to some sound-proofing foam pieces. They are shaped like this VVVVVVV and are a foam material - I might try to wrap the fan up in that stuff with the pointy sides directed at the fan. I think that would probably work well! I will try it out and let you guys know how it works. Maybe even wrapping it in heavy cloth or something like that. I think I will just try multiple things and see how it goes.

 

[RB56]

It might help to consider that we have 3 options for most industrial noise reduction. One is vibration damping. This is most often useful when sheet metal or plastic panels are resonating. The target here is structural transmission of vibration.

Air borne sound is the other common problem. The two tools we have are blocking and absorbing. Blocking requires mass. We need to build a limp wall to enclose the sound. Lead and mass loaded vinyl are most common materials for that application.

Absorption can be difficult in tight spaces. To absorb sound the material needs to be 1/4 as thick of the wavelength of the frequency you're targeting. Means absorption is much easier for high frequency than low frequency noise which can require materials that are many feet thick.

I've made a bunch of acoustical mods to my room using materials I bought from a place that sells acoustical materials for cars.

 

[sub]

It might help to consider that we have 3 options for most industrial noise reduction. One is vibration damping. This is most often useful when sheet metal or plastic panels are resonating. The target here is structural transmission of vibration.

Air borne sound is the other common problem. The two tools we have are blocking and absorbing. Blocking requires mass. We need to build a limp wall to enclose the sound. Lead and mass loaded vinyl are most common materials for that application.

Absorption can be difficult in tight spaces. To absorb sound the material needs to be 1/4 as thick of the wavelength of the frequency you're targeting. Means absorption is much easier for high frequency than low frequency noise which can require materials that are many feet thick.

I've made a bunch of acoustical mods to my room using materials I bought from a place that sells acoustical materials for cars.

Thanks for the info. Something I had planned on doing was wherever I mount my fan I will have it on some kind of rubber material or some shock absorbing foam or something like that. I think that with the combined insulated ducting and the foam surrounding the fan will reduce noise considerably.

I'm pretty excited, too, because I am switching to LED which means I may be able to get away with running my Soler & Palau TD-125 on low, which is practically silent to begin with. I think the hardest thing to deal with would be the rushing air from the fan, not the fan's vibrations or moving parts - I wonder if there's much we can do about that. Ah well not really a big deal.. I just love the idea of having a hidden little grow box.
I also want a hidden room behind a book shelf and shit like that.. always have. I just really love the idea Totally not needed, though!

 

[adrenaline]

I saw this online, my store doesn't stock it but can have it delivered to the store. Looks promising for the inside of my cab, maybe yours too.
Pricy though.

http://www.homedepot.com/p/Unbranded-dB-3-4-ft-x-8-ft-Acoustical-Barrier-DB348X96BX/100663624?cm_sp=BazVoice-_-RLP-_-100663624-_-x

 

[RB56]

I saw this online, my store doesn't stock it but can have it delivered to the store. Looks promising for the inside of my cab, maybe yours too.
Pricy though.

http://www.homedepot.com/p/Unbrande...00663624?cm_sp=BazVoice-_-RLP-_-100663624-_-x

That's a recycled EVA barrier. It's too stiff for some applications but is great for construction. Best use is inside walls as you build them. You want to hang it with anchors at the center of framing studs so it has an airspace on both sides.

Important consideration when adding a barrier is that you need to at least double the mass/area of what was already there to gain an easily audible improvement.

 

[JKD]

Acoustic foam is a product specifically made for reducing noise transmission.
Carpet underlay and also egg trays are reasonable, but less effective alternatives.