Trying to choose a box design

[vike4511]

I have two designs in mind, one I posted earlier with a port back up the center of the box tuned to 31 hz. The other is this one with the port across the bottom, and tuned to 33 hz. I'm just wondering if there is a benefit to port placement between the two boxes and which one would you recommend I build. Thanks

This is the box tuned to 33hz