Tune it to 20 Hz using a 2" Diameter port. In order to get 20hz it would need to b 5.29 inches long
To keep port mach to an acceptable amount for a common chamber box for those 2 12's you would need a minimum of 25.64 sq in of port area or a 5.7" round diameter. Anything less and you'll get some nasty port noise
So if the Xmax is a larger number i need to make the ports wider? Cant i jus use 2" ports the whole time or i have to make it larger
you could use 2" ports but you'd have to use multiple ports.
the mo mo site gave directions on how to make a ported box but it says it would b tuned to 40 HZ then Fe3 would b 36.5 hz. This is using a 4in diameter port 10 inches long. Could i use this plan and tune it down a bit
by making the port longer you could change the tuning frequency but don't just guess at the length make sure you run it through a calc.