Mark,
The EV DH1 drivers are an old driver. Minimum crossover at 500 hz. They are rated at 75 Watts.
The Horns are probably EV also. The DH1 drivers were suggested for these EV horns:
HP 420
640
940
1240
4020
6040
and the 9040
I'm guessing that the horns in your photo are three of these, above models.
The TL 806 numbers are box models from EV for those that wished to build their own Cabinets. Plans are still available for many of their designs . Your numbers do not directly correspond to EV's numbers. EV had only two cabinet designs with the "TL 806" designation. The first had only one 12" driver, and the second had FOUR 12" drivers.
(Your cabinets have two drivers in them)
These box designs did NOT have a midrange driver in them, they were designed as part of a two-way system.
So...I'm guessing that someone took a design and corrupted it.
The eyebolts used for hanging the cabinets are an unsafe added feature, they should have never been hung.
These horns and drivers were considered professional gear in their day, but, by today's standards, cannot compete.
Cheers,
Hammer