Sony APM-66ES

Available in quite a few versions, depending on the market, the APM-66ES was the last "real" APM before the tiny boxes took over.

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 original APMs - all diecast frames nevertheless.

Like the APM-77 or APM-4, the 66ES also was a bass-reflex... depending on market : 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 while the european equivalent (black or wood) was a sealed design !

The japanese and USA versions have two front pots, which the european APM-66ES doesn't have. And, even more puzzling, there was an APM-66ESG version.

The export APM-66ES (whatever the version) was available either with wood veneer (rare) or black (common).

The b/r version corresponds to the "Type 1" in the 1986 manual.
The bass surrounds were of (poly)urethane until serial numbers #302 600 (CA, AEP, UK and E models) and #800 440 (USA) ; later numbers used synthetic rubber.


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