[HiTech RedNeck]

Here's a "philosophical" question that I could answer at least part of in a
minute with an empirical test, but I want to see how people think about it.

In the conventional single ended tube audio output stage, having a
conventional audio output transformer the ends of whose primary is wired to
B+ and the output tube plate, and the ends of whose secondary is wired to
the speaker (don't throw in any complications like additional circuitry on
either side of the transformer; keep the tube in conduction at all times,
i.e. class A operation; and provide an input such that the output stays
within the rated frequency and power range of the speaker and transformer),
WILL THE INSTANTANEOUS PLATE VOLTAGE EVER RISE ABOVE B+? Or will it remain
in the range somewhere between B+ and zero volts, with a midpoint
approximately halfway between the extremes, a midpoint that depends on the
amplitude of the output signal?

But if it rises above B+, why? And then why don't tube manuals reflect the
maximum instantaneous permissible plate voltage, but rather what looks like
maximum quiescent voltage, when they give "absolute maximum" figures for
plate voltage? (Yes, I know that the data for television horizontal output
tubes generally give such instantaneous maximum plate voltage information,
but these tubes cut off conduction in normal operation and they normally
operate into an underdamped circuit which rings, i.e. flyback, when the tube
cuts off.)