I was fortunate enough to find a pair of these beasts.... I have semi-restored them back to life. I mean the Altec 604-8g sounds great. Now these have the time aligned crossovers which are giant.
It's almost like a crossover in the front and one in the back....
Anyways, I'm not getting anything from the tone controls in the front. I will post pictures later today when I get home from work, but I was hoping that someone possibly had a schematic???
These crossovers sport (3) light bulbs (H,M,L) which are like 6.2 volts each.. I have never seen anything like this.
I have recapped the back half of the crossover.