Or you need a foam filter like you get in some vacuums, and a higher
pressure fan to keep the air moving, but his does then make it essential
that the is easy to remove and clean.
Brian

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The Sofa of Brian Gaff...

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On Friday, 31 January 2020 21:14:04 UTC, ElBelle wrote:
replying to harry, ElBelle wrote:

What can be done to reduce / get rid of traffic noise through the duct?
As we
have this issue at the moment!! Thanks

An airpath with some 90 degree turns can greatly reduce noise. The more
such turns the better. The baffles used to contruct need to be stiff or
damping enough to not transmit the noise straight through them.


NT