In support of your posted premise "do it yourself," may I humbly suggest you delve into one of the Kings of DIY's website "www.geocities.com/jonrisch" . You will find a plethora of diy acoustic projects to occupy yourself. I built his bass trap panels and found them most excellent. While they will not have as great an effect as pricier equalization solutions, they are much better than simple foam, quilts, etc. The foam & fabric route is only effective in the higher frequencies, whereas the bass traps affect much lower frequencies as well. How low depends on how thick you construct them.
"do it yourself" acoustics
I have a 13'x13' room. In this room, I have Vandersteen 3a speakers driven by a 100wpc Aria amp through a CJ Art Pre. Music is despenced through a CJ DV-2B Disk Player. That said, I am looking for "do it yourself" ideas for dampning this chamber of echos. Listener's fatague is cutting into my listening time. Please diregard poor spelling. Many thanks. Steve