In our last thrilling episode, our hero was backed into a corner, and...
Followed by an (agreed with) suggestion they be oriented vertically, directly to the outsides of the 511s, next to the wall(s).
Perhaps a bad assumption on my part they'd be mounted on a baffle, so I'll rephrase that to "common plane of being".
Never mind that. The point was it would take a boxfull of caps (or the previosly suggested active delay) to stack up the needed phase delay.
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