Very interesting post there rmax. After a bit of googling I now see what you are talking about. Bit I wonder what the design creators implemented to give greater efficiency?

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mine is on the exhaust....and is very effective....but then that is the way my system was designed to function as well....so I can't speak to the other approach.

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Ride hard, Ride long....git put away Wet each and every time....no holdin' Back.....enjoy the journey ...... cuz that's ALL there is! Walk on and walk tall folks!

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You have me thinking too. If you Non-Bi-Directional filter works in a direction it shouldn't, then maybe many or all filters can be used in either direction. There are of course other questions that need to be brought up before one changes their setup, but if it doesn't matter if the can is on the in or out, and on the out is quieter, then this is ideal info for those how suffer with noise pollution from their indoor garden.

My setup is quite noisy. I can't hear the front door knocking from inside the grow space. I have a room within a room type setup, making my garden very much self contained. I do have the option of adding another filter outside the grow space to dampen the sound if it was an effective measure.

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Do you know who manufactured your filter? I'm trying to establish as many ways as possible these things can be used regardless of what the manufacturers say.

What size filter(s) length; diameter; and duct opening do you/we all use?

thanks

Does Anyone Use A Silencer!?

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thinking of purchasing a phat filter ...anybody on here know anything about these types of filters?

I think i can help - the reservable carbon filter is so you can flip the carbon filter the other way to ensure you've used all the filter regardless of whether you are sucking through or blowing out.

The carbon filters are designed to be on the end of the exhaust (so you are blowing air through it) BUT a lot of growers suck the air through that way you can put it on the inside of your box to keep it more stealthy. That way - there isn't a huge filter sitting beside your "wardrobe".

So filters ARE designed to be blown in to then? And sucking is just a choice on the growers part?

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that is my understanding but admittedly my understanding is very limited

you could contact the manufacturer of any filters you are considering and ask them.

whats a good yet cheap filter?

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We must have clarity and peace of mind in order to tap into our Greater wisdom and knowledge. my 1st indor grow! Bubbler FloraNova & Floralicious my 2nd simultaneos grow Lowryder2 and AK47 x Blueberry

whas your price range?