EV Builder's Plans - PDFs
The TL806 plans spec the fb as 53Hz with the port cover on, which should be
usable for bass guitar. I purchased my lumber the other day, and I'm hoping to use my brother-in-law's tools sometime this weekend to build my box. I modified the dimensions so the overall width is 20.5" with the cabinet on its "side" instead of 17.75" (so my rack/head sits nicely on top). Since I'll have extra room on the baffle with the larger width, I'm hoping to have room for a tweeter on there, but I think I'll save that for the second one I build.
I'd like to know what EV took into account when calculating the depth of these slot vents, because they're a bit different (generally shorter) than what you get from most formulas.