The other locations anywhere in the front of the room have the null also. I had bags of playsand stacked up ready for use and my builder took them and used them for paving steps bcause nobody wanted to purchase more sand or would help carry it down the hill. They took my leftover and tossed it. The 3/4 plywood stage is filled with some pink insulation. If sand will help the null, I could give it a try but it would be some trouble to accomplish. I have seen that being done before so I might have the motivation to do it. I'm not sure if that is what causes it.
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The two lower corners in the rear I have not tested since adding more room treatments. The other side similar to the one shown has the entrance door next to it. This is where I origanally placed the subwoofer (pictured) using a crawl test, before there was any framing, located in this corner. I had compllaints in the back row that it was boomy there and the room treatment phase then began. I have not tested the location.
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This is where the subwoofer was tested at the top of the thread with it located on the side of the room. I don't see a null at this location... so I thought it might have been a good location? Having a peak a few dB higher to eq is better than having a null right?
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