Export-only and later version of the APM-66ES with puzzling cone and aluminium dome for the mid and high drivers, this corresponds to the "Type 2" in the service 1986 manual.
Also a bass-reflex !
The original japanese APM-66ES (black) had its b-r port vertical next to the mid driver, the USA equivalent (wood) had it there too, the EU equivalent (black or wood) was a sealed design... and this ESG version brings its b-r port back where it was on all original APMs : under the woofer !
The woofer however is very different than that of the APM-77 : there is only one motor, linked to the flat diaphragm with eight damped tubular sticks. So the 66ES is a halfway between the more conventional Technics honeycombs and the real APMs. All diecast frames nevertheless.
It also adds two front pots, which the previous EU APM-66ES models didn't have (but the USA did). And the enclosure isn't as tall, is less wide and less deep.
Some marketing exec's really wander around, sometimes. Engineers, too.