[Chris Hornbeck]

On Sun, 7 Dec 2008 21:28:20 -0500, Charlie Olsen
wrote:

And it has a "speaker impedance selector" ?

This is typically a choice of taps on the power transformer's
secondaries to vary supply voltages to the output stages.

As for ratings, maybe the reason they didn't rate at the lower impedance is
because they could not make the frequency response or distortion figures.

FTC preconditioning specs were notoriously dangerous thermally,
requiring long periods at high thermal loads (less than full power
outputs can cause *higher* heat loading - strange but true).

An honest amplifier manufacturer was typically limited more
by FTC protocols than by frequency response or distortion,
in modern-era amplifiers.

All the best fortune,
Chris Hornbeck