# Duct Muffler?



## rednose (Jun 10, 2012)

I am wondering if anybody uses these thinking about buying one because the fan is in my bedroom and I need to cut the noise down on the fan are the duct mufflers worth buying or should I try and figure something else out?


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## dman1234 (Jun 10, 2012)

I bet someone uses them and will answer, but if not and your cooling/exhaust is powerful enough you can buy a speed control for your fan and slow it down or i think people use insulated ducting to control noise. jmo


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## rednose (Jun 10, 2012)

the fan is 170 cfm


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## Old_SSSC_Guy (Jun 10, 2012)

one of the blower speed controllers will do the trick.  i run all blowers (not fans) on speed controllers and scale them back about 50%.  runs almost silent then - but will only move 1/2 the air.  in your case running at 50% would give you about 85cfm.  i just bought another 2 of the controllers for $43.


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## rednose (Jun 10, 2012)

Old_SSSC_Guy said:
			
		

> one of the blower speed controllers will do the trick. i run all blowers (not fans) on speed controllers and scale them back about 50%. runs almost silent then - but will only move 1/2 the air. in your case running at 50% would give you about 85cfm. i just bought another 2 of the controllers for $43.


 
So would 85 cfm be enough to move air if i went with a spped controller im running a 400 watt hps


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## Old_SSSC_Guy (Jun 10, 2012)

depends more on the room size rather than light size.  one rule is to take the cubic feet of the room and divide it by 5 (so you exhaust the whole room every 5 minutes).

so a 10' x 10' x 8' room is 800 cf - divided by 5 = 160 cfm fan
or a   6' x  6' x 6' room is 216 cf -  divided by 5 = 43 cfm fan


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## rednose (Jun 10, 2012)

Old_SSSC_Guy said:
			
		

> depends more on the room size rather than light size. one rule is to take the cubic feet of the room and divide it by 5 (so you exhaust the whole room every 5 minutes).
> 
> so a 10' x 10' x 8' room is 800 cf - divided by 5 = 160 cfm fan
> or a 6' x 6' x 6' room is 216 cf - divided by 5 = 43 cfm fan


 
Thanks alot for your replies the speed controller should work just fine the room is 2x4x6


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## rednose (Jun 10, 2012)

Will any kind of speed controller work with any kind of fan?


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## Old_SSSC_Guy (Jun 10, 2012)

yes on the room size rednose.  a real quiet small bathroom fan might do the trick for you.

i tried using a few different cheap speed controllers from the hardware store (like made for ceiling fans) and they did not work reliably for me.  now i stick with this generic china one that seem to be sold everywhere, but with different labels stuck on them.  they sell for about $22-$25 on Ebay and at HTGS (my current fave grow shop).  search in ebay for "speedster fan".  that's one of its brand names, you can also get the same one from harbor freight.   like i said earlier, i just ordered 2 more of them.  they are cheap for what they do safely and worth it.

hope your grow goes great for you!


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## rednose (Jun 10, 2012)

I appreciate it


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