[Big Bad Bob]

On 11/15/10 23:19, Paul D. Spiegel so witilly quipped:
A common configuration for an output transformer secondary (a la Dynaco)
is C-4-8-16. The four ohm tap is roughly the mid-point of secondary.

If you connect one 4 ohm load from C-4 and then another 4 ohm load from
4-16, what would the overall load look like to the output stage? Would
it make a difference if you ground the 4 ohm tap instead of C?

This could be an interesting way to bi-wire a speaker.

What do RATs think?

transformers and beam-power pentodes are expensive. I suggest NOT doing
that. Your total load will be twice that of a 4 ohm load on the 4 ohm
tap because you're loading it TWICE instead of once. The end result at
full power would be pink plates and possible burnt windings. The magic
blue smoke won't go back in, by the way. You'll have to get "a new one"
(whatever blows up first).

You could wire ONE of the speakers on 4-16 but I see no reason why you
would want to. Instead, wire the speakers in series and use the 8 ohm
tap, or (if whoofer/tweeter) use series crossover cap/coil and phase
invert the tweeter.

Or keep on hand a stock of tubes, transformers, filter chokes, and solder.