I pulled the low driver out of that "Altec Lansing" 312. The flimsiest Harmann Kardboard 12" 18 ga. frame they made (one would hope) and a wimpy (10 oz. ?) ceramic magnet with "Super high-temperature pure copper voice coils". 22 ga. wire connecting "a multiple element dividing network to maintain precise frequency distribution" consisting of a hot-melt glued coil and a cap or two.
The surrounds have mostly disintegrated after 20 years. They actually still sound fairly good for what they were and cost at the time. I don't mind listening to them for hours. I don't say that about 75% of what I've heard, and that includes units well above my best budget.
I'd go for a Radio Shackish UPgrade, but even they don't sell a lightweight 12" woof woof any more. No budget for real drivers much less better cabinets at present. Tough to match efficient bargain drivers to suit these days.
Can a shop glue a new surround on these?
Martin W.