By using the Fb formula at JL Audio, and running it twice -- once for each 1/2 Vb, I came-up with 2 X 2.0 in. ID X 5.25 in. long ducts -- still tunes 3.8 Ft^3 to ~ 28 Hz, as called for in PiAlign for a single EV 12TRXB.

Q: Does doubling the Vent Area effect Damping Bandwidth? Real-World output?? Sound Quality???

Respectfully,

Stephen ; )

• Fb formula at JL Audio