Home made absorption panels.....


I would like to hear some good inexpensive ways to make absorption panels, particularly at first point of reflection.

Thanks.
capt369
Drapes work well for me. And the old stand by, bookshelves filled with books are effective too. Only thing is, if you only own a few books, buying a bookcase full can cost as much as a nice amp!
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One problem that I have is that one ref. point will be on a sliding glass door covered with vertical venetion blinds. Maybe I can build something on a floor stand. Any ideas?