Interested in SA xv3 15 d2 but need box advice

[shredder1 10+ year member]

@shredder1 hey bro, if I go with the Zv6 15” d2, what mods would I have to make to the current box to get between 29-30hz? I was thinking about mounting the sub external but then the magnet would block my view behind. I was thinking about A) cutting the top off and gluing more height so the sub mounts in the box or B) adding ___” of a MDF rings so the sub sits inside box.
Do you need more pics of the custom box that sits on an angle behind the 3rd row?

I'd just say invert the sub to gain a bit of volume, the fixed port area should be tuned lower in the greater volume.
Unless you enjoy box surgery I'd say its a no-brainer. On your power I feel the Xv3 would be a better choice myself. You're a little short on port area but setting your SSF should keep those velocities around tuning in check on your power. Inverting an X won't be quite as in your mirror as a Zv6. Those things are about as big as 3" coiled subs get.
Otherwise I'd grab a specific design for that 3rd row location and plan on a bit more power to get the performance on par with an Xv3 in your current enclosure out of that Zv6.

As far as adding rings I'd suggest 2 to add volume (.18ft3)... that should cover the driver differences plus a little extra. 3 would add .27ft3... so you can cut an extra and experiment. Without dissecting the design (No thx) I feel that would actually be the best route. 2 or 3 rings added just may land you right at 4.25ish @ 30ish hz.

 

[West1 10+ year member]

I’m leaning towards the xv3 tbh. I’m also leaning towards adding the rings or if I can figure out how much taller to raise the top portion of the box. It’s all MDF so it should glue down pretty well.