I have used a BFD for the last year or so to tame some room modes. In particular, I have a 6bd hump at 35 hertz and a +12db hump at 47 hertz. These have been present in any sub I have used, so I know its a room mode. My problem is that I cannot get the +12 db hump at 47 hertz flat without using -20 db or so cut at 47 hertz. Why is it taking more than 12db of cut to counteract a 12 db hump. The other problem is that if I do add in enough EQ to make the hump completely flat it sucks the life right out of the music. Could this 12db hump be an artifact of my measuring process. I am using sine waves and a rat shack SPL meter. My guess is that the constant sine wave energizes the room mode in a way that music, which is transient in nature, does not. Should I just adjust the eq to subtract 12 db from the hump and not worry about the response being flat? BTW, the 6db hump at 35 hertz hump is easy to equalize with no penalty in sonics as a result of the equalization.