I have been trying a lot of different sub setups with my 80PRS, and I have a similar problem:
With just one dvc sub the auto ta correctly detects the subs distance as 148 cm. but with 2 subs installed running stereo in the same IB the left side sub is still correctly detected at 148cm but the right side is detected as 250 cm. away, when its really only 153 cm away from the mic.
I figured standing waves inside my car screw up the auto ta, so I tried manually setting both subs at 148cm but I ended up just parallel connecting the 2 dvc subs in a mono setup. This way I get more power from my small RF amp and the auto ta seems to work correctly
150 or 153cm doesn't matter. Just run them as mono.
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