I am building a sealed enclosure for a Neo8 line array and want to make sure there is no back reflection which might travel through the thin membrane.
I usually line my enclosures with 5 mm wood felt (the green stuff that goes underneath floor tyles), stuff 2/3 of the enclosure with rock wool (higher packing density in the rear), with the fibers oriented towards the speaker to provide more flow resisatance. Then I cover this with one layer of wood felt both to keep the fibers where they are and to provide additional flow resistance where velocity is high. The last third right behind the driver is empty because want the driver to braethe freely.
I wonder if I can improve on this, e.g. one or several kinds of foam. I gather rock wool works through flow resistance. How does foam work? Also flow resistance? Or just plain vibrating mass that absorbs because of internal friction? Does it absorbe more or less than rock wool?
I usually line my enclosures with 5 mm wood felt (the green stuff that goes underneath floor tyles), stuff 2/3 of the enclosure with rock wool (higher packing density in the rear), with the fibers oriented towards the speaker to provide more flow resisatance. Then I cover this with one layer of wood felt both to keep the fibers where they are and to provide additional flow resistance where velocity is high. The last third right behind the driver is empty because want the driver to braethe freely.
I wonder if I can improve on this, e.g. one or several kinds of foam. I gather rock wool works through flow resistance. How does foam work? Also flow resistance? Or just plain vibrating mass that absorbs because of internal friction? Does it absorbe more or less than rock wool?