I'm hoping for a software solution for my HTPC to equalize my music.  I will have to place some nice 3-ways near a wall and this is unavoidable.  I want to be able to tone down the bass which I know will probably be accentuated by the close proximity to the wall.  I know iTunes has an EQ, but I currently am using Vista Media Center and have about 400 CD's already ripped to my hard drive uncompressed.  
I'll be feeding the output via USB or optical to a sound card (possibly an internal sound card). Any ideas?