This above box is used elbows to catch and absorb the sound energy in the acoustical foam. It does't have a great deal of insulation.
The image above uses a flax duct running in between the baffles. And uses insulation to absorb the sound. If one is using insulation One must use something on top of the insulation if they don't want to breathe fiber particles.
A baffled box or acoustic box looks like that this has insulation. The only thing is no one wants to breathe the fiber particles coming straight from the vent. And as i see somewhere that the length of the deadening vent needs to be three times the diameter of the hole. So if my hole will be 4 in diameter the length needs to be 16. However what if we can include the total length of the duct till the end.
this image is also not three times the length of the diameter on each row. The sub total (when you calculate the whole length of the air flow till the final outcome) is probably so...
The above is Ted White'
So im asking you do you know if its the same thing. Producing the same results.
This is findable in quite a few sites
My question is which one is better . And if i want to imply the four elements of Dead Vent Elbow Mass Damping Change in air volume, i can make it with the acoustic/baffled box also. Or it doesn't have this much insulation as Teds White' suggestion
I think to have a powerful fan. Because 90 degrees elbows takes slows down the air. However why do we need an inline fan.
I dont find any STC on that kind of traffic box
Edited by nashoomoo - 6/13/13 at 8:02am