snip a bit,


But the grid current initially flowing in the CPI stage was limited by the
cathode R of the stage. And it wasn't for a long period.
I have used SS rectifiers, the voltage comes up high within 3 seconds,
and sure that direct coupled grid goes high, bit it comes down
to about 100v ok after 15 seconds.

It's not challenging at all today to design a power supply without
tube rectifiers, that cycles the voltages needed for operation of the
amplifier in the proper order and moreover ramps each up in a
controlled, benign fashion. It is simple cookbookery, no engineering
per se is really needed. Most tube builders are electronically below
any reasonable fitness standard, however, and so it does not happen.

B+ ramp ups don't need to be installed. tube amps work OK without them.
But all that needs to be used is an inrush current limiting R so the mains fuse
value
can be kept as low as possible, and therefore provide adequate protection
if the other measures in the amp fail.


Such a power supply would be good for running slightly modified
vintage amps, test bench work, or running radio apparatus as well as
hi-fi.

But 99% of tube amp buyers don't tinker with power amps.



When the Williamson was turned off, it fed a large very low frequency
power pulse to the speaker.

This slow pulse from the collapsing B+ voltage didn't last long.

Many Hi Fi speakers couldn't take this
very low frequency pulse and blew out.

Its no worse than running the amp to clipping with a signal at LF.

History records few if any such blowouts.

So why did you suggest thse pulses would blow speakers?


Snip a bit more


The resulting HF response is fabulous, and a reason why tube amps are so
detailed and
fine sounding; they have no problems with musical transients.
It does depend on clipping never occuring, but ppl with hi-fi systems
never go near clipping.

Maybe they -shouldn't-. They do!

Nobody I know uses their amps at an average level much above 1/20 the maximum
power at onset of clipping.



Snip a little more,


Many W amps were made and worked as W said they would.

Many were. Many more were deviated from and still usually worked. In
the US no amateur wound his own output transformer.

Huh?
I have had quite some emails for advice about winding OPTs.

Some ppl are doing it.

Most had a pet
builder whom they attributed Godlike powers to, such as Ercel Harrison
at Peerless, and would use their product over all others based on some
mantra. Much of the "secret wisdom" of these "gurus" is quietly sitting
on library shelves if one knows where to find it-a hint: The U.S. Navy
is the most ardent audiophile organization in history.

Navies were not usually interested in purchasing audiophile grade OPTs for their
aircraft carrier PA systems.



snip more,


The output stage:

In the American version of the Williamson, two 807's, triode connected
were connected in push pull and fed into the primary of the Partridge
output transformer. The pair of tubes were cathode biased (together)
with an unbypassed common cathode resister. This arrangement cost
output power and high frequency response.

Wrong.
Correct! He's on crack.

Prove you are correct then.

Snip the rest, since I think I have addressed the contentious
issues.

Patrick Turner.