By the way, the t14/1 is a fairly unimpressive transformer, especially in later vintages, as I'm sure Oliver will verify.
Sorry to correct for a typo, but the word "ratio" in Oliver's third paragraph, the one beginning in "AKG utilized..." should actually be "radio". Most of the gear we all lust for was critically designed in the early days by some mighty high flyers in both acedemia (when it meant something) and broadcasting.
The guys in the 30's, 40's, and 50's really knew what they were doing.
By the 60's and 70's, things started slipping, or maybe in reality, commerce caught up with them, and true engineering, from first principles fell by the wayside.
So a transformer with inferior iron, that intrinsically did a part of the low frequency filtering required by the broadcasters was used instead of a wider bandwidth part, with appropriate filtering. The difference? While the transformer will limit the low end, it does that and adds distortion caused by core saturation, as well as amplifier distortion artifacts caused by the lower inductance of the smaller transformer, but filtering with a capacitive circuit will add virtually no distortion to the active circuit, and in fact protect the transformer from large low frequency signals. To a degree...
All engineering decisions are tradeoffs of course, but I think this is a good example of the beginning of the slide.
Just think about it, what has AKG done lately that's really good?
The later C24's are certainly pale imitations of their former glory.