Hi Peter,
Considering that we are comparing tie type of audio stage in this 655 to other Philcos and other amplifiers, it is likely appropriate, especially that we were comparing the 655 to the 645.
Again, great info and conversation!!
Yes, John. It is by comparing these two models that it is clearly visible that in the more expensive Philco 655 model, two 6F6 lamps are used in the output stage in a triode connection, while in the cheaper 645 model we see the same lamps, but in a standard pentode connection. So we can conclude which type of connection is best for correct sound.
For those wondering what " triode inclusion" is: it means "triode arrangement / triode conenction".
(The reason of this is that in Russian "включение" means both "hook-up arrangement or mode" and "inclusion").
BTW, one of the advantages of using pentodes in whichever mode is that they, simply speaking, are still widely available (and if needs be, are arranged as triodes) whereas the triodes ars simply much harder to find.