[Wayne A. Pflughaupt]

I was wondering if it was possible to bring everything down so that it is in-line with the dip i.e it doesn't become a dip any more.

As soon as you turn your sub up to account for the ~35 dB loss it may come right back.

Not to mention, we’ve seen here that such drastic cutting can cause other problems. For instance, you could end up with too low a level to drive your sub to its maximum output. Or get substantially increased noise from having to turn the sub’s gain up so high to compensate.

This is probably going to be difficult if not impossible curve to equalize. The “distance” between your relative low area between 60-100 Hz and the peak at 39 Hz is just too great. I suggest trying other locations, such as a corner, if that’s not where it is now.

Regards,
Wayne