Re: front-loaded?
Just like it sounds. The speaker holes in the cabinet are routed or recessed so that the speakers can only be installed (loaded) from the front. My VHT is front loaded. There is no rear panel. It must be glued/tabbed into the side wood. You can take off the input jack cover, and pear inside. But the tolex is continuous from the sides all over the back.
Some say that front loaded cabs sound different than rear loaded one. Maybe someone with more experience can chime in on that.