[Wayne A. Pflughaupt]

I Still find a very annoying loud vibrating resonance when music gets down in the lower frequencies (my guess is 30hz and lower). It sounds as if it has jumped in volume 10dB+. I can visually see it in the waterfall as well.

My question is, What can be done to tame this beast?

Like the others who have commented, nothing’s jumping out at me that would explain the loud jump in volume that you’re hearing. The 20 Hz bump should not be audible with music. However, most music has a lot of energy in the 50-80 Hz range, where your baseline chart does show elevated levels.

You indicate that you have an FBQ, but I’m kinda curious about your “corrected” chart. The dotted line indicates that it’s what REW is predicting equalized response to be, not an actual sweep of equalized response. So do you even have an equalized graph for us?

If all else fails in tracking down the “10 dB jump in volume” issue, try running per-frequency sine wave test tones. You can download some at our Downloads Page and burn them to a CD. That should make it obvious where the problem is, as you’ll hear a severe increase in SPL when the offending frequency plays. It may be a good idea to record the SPL level of each tone, for later analysis. It’s highly possible that the problem is a range of frequencies, not just a single one.

Question, I am setting my sub based on my receivers test tones which leaves it well above my mains. Should I just use REW and leave it at that?

REW is an aide for equalization, which has nothing to do with relative levels between the mains and subs. After equalization, set the levels with the receiver’s test tones as usual.

Regards,
Wayne