It's unfortunate (or fortunate depending on your perspective) you found these problems. I wonder now what my Onk's pre-outs are like.
I don't know what you mean by the quarter wave pattern. I wanted to make sure I minimized a null in SPL at my MLP at the 80 Hz crossover. In my Onk, I set the distance between my sub and the MLP, secured the meter at my MLP, and established the correct polarity by playing an 80 Hz sine tone. I set the polarity such that it resulted in the highest SPL. Then I increased the distance setting until the SPL went to a maximum. Finally I adjusted the phase to ensure a maximum SPL. My phase is set to about 60 degrees. I saw no difference in SPL between 0 to 60 degrees. After 60, it started to dip. Coincidentally, one of my fundamental room modes is at ~80 Hz due to my ceiling.
My sub is 9 feet away from my MLP. The distance setting that resulted in the highest SPL was 14 feet. I thetherefore had to add 5 feet to account for DSP processing delay. This is about 5 msec at 80 Hz.
