Ok so after some investigation and analysis Brian Ding acknowledges that the the amp limit on the top end is about 150 hz. My toppers go down to 200 hz. But he thinks that the major culprit is a cancellation in the room. He does believe that I may be able to "smooth" it out somewhat by experimenting with room placement. Currently I am 3 1/2 ft from the front wall and 6 ft from the side wall. I remember reading where it said to start close to the front wall and move forward in 2 inch increments until I get the best spot. Any thoughts on this?
In the open baffle configuration these are supposed to play up to 300Hz. I just checked out my H-Frames. I didn't turn on the power amp to the top sections so only the H-Frames were playing. I used discrete sine wave tones from 20Hz to 400Hz. The tone files I have include 100Hz, 250Hz and 400Hz (nothing in between). With the crossover turned all the way up (pointing at 150Hz), output was solid at the listening position to and including 250Hz. While audible, 400Hz was significantly diminished.
As long as your amps have the servo control board with the OB circuit for the SW-12-16FR drivers and everything is wired correctly I'm not sure why you are not getting this type of output.
Unless you are using a version of the A370 amp that has both "Line In" and "LFE In" RCA jacks (A370-PEQ3, -XLR 2 or -XLR 3) and you have the RCA interconnects plugged into the "LFE In" jacks. When this happens the crossover control knob is by-passed. The "LFE In" jacks assume you are setting the crossover points in a home theater receiver.
If you are using the A370PEQ version of the amp this is not an issue because it does not have any "LFE In" inputs.
One way I was told to troubleshoot if it is a speaker issue or a room interaction issue is to stick your ear right up to the opening (or even a little inside the opening) of one of the drivers and play the tone. If you can hear the tone with your ear right at the opening, so there is no chance for any room interference, but cannot hear it (or it is significantly diminished) at the listening position there is a room issue. If you can't hear it right at the speaker opening it is a speaker issue.