changing ports


Hello All,
I'm working on a single driver design, and I want to try using a ported dual chamber box. The dimensions work out at 2 1/2" in diameter at 3/4" length using a single port box. Anybody know the formula to convert one vent to two? I would like to keep the vent length at 3/4" as that's also the front panel thickness. (No, I'm keeping my Pi's. I just acquired a pair of Moth Cicada drivers and want to play with them.)
Thanks in advance,
Steve


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