[quote author=BWR link=1136306988/0#6 date=1136864064]
I guess I missed it. The author specifically cites output impedance as the determinant of damping factor. From the 4th paragraph: "The lower the plate resistance, the lower the output Z. The lower the output Z, the higher the damping factor. The higher the DF, the better the bass performance (in most cases)." The whole notion of damping factor is misleading for two reasons: no speaker is a fixed 8 ohm load and an amp's output impedance is a function of frequency. So the damping factor is constantly changing as the input signal.
-- Bob
[/quote]
The final sentence of the cited paragraph, and the first sentence of the following:
Quote:
" So in a single ended amp, the DF flip flops on the fly with the plate swing. In a PP amp, one tube's current is swinging high while the other swings low, which yields a constant average of the two."
The point I was attempting to make by the above quote, and on which I think we agree, is that DF is one of those spec's that mean a lot less than they might, in the real world.
i.e. the range of potential speaker & interface impedance (combination of R + I +C) is so wide, that it's probably meaningless to quote DF for any amp ( and specifially a SE ) except at a fixed impedance and frequency. Since the music / loudspeaker interface present far more complex a load than that (think of is as a type of global feedback), it (DF) alone can't necessarily predict the sonic outcome. Some listeners use high DCR speaker wire
specifically for the purpose of altering the "loudspeaker Q / amplifier DF" equation to their taste.