Freddi, I'll have to pop the backs off them again and take some pictures. IIRC, mine don't have a very big shelf, if any...but everything in the back chamber is covered by fiberglass insulation. I'll remove that and snap some photos.
I've run my hand across the upper panel on the front of the speaker, and there are no slit ports, a rectangular port, nor does it feel like someone had even patched up a hole or two...so I'm thinking that they have been sealed up since they are made (who knows when).
I wonder however, if these speakers weren't modded by someone in the 60s-70s timeframe. Given the fact that the drivers date from the late 60s into the early 70s, and the insulation that is in there, looks rather modern...
I've run my hand across the upper panel on the front of the speaker, and there are no slit ports, a rectangular port, nor does it feel like someone had even patched up a hole or two...so I'm thinking that they have been sealed up since they are made (who knows when).
I wonder however, if these speakers weren't modded by someone in the 60s-70s timeframe. Given the fact that the drivers date from the late 60s into the early 70s, and the insulation that is in there, looks rather modern...