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Phil Allison Phil Allison is offline
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Default Impedance Curves


"BobW"
"Phil Allison"


Pretty interesting. It would have been nice to also see phase angle, but
what the heck.


** Well, when the curve is rising - the phase is inductive.

When it is falling, the phase is capacitive.

When it is doing neither - the load is resistive.



That rising impedance of the Quads at low freqs is obviously the primary
inductance of the step-up transformer, and the descreasing impedance (at
about 6KHz) is the capacitance of those wonderful elecrostats. I wonder
if the rising impedance at 20KHz is some type of amplifier-saving
inductor, or maybe it's the leakage inductance of the transformer?



** The latter - for sure.


There's a need, imho, for a direct-drive amplifier for electrostat
loudspeakers.


** Not IMHO.

Well engineered transformers do the job very well, at low cost and with
total reliability.



....... Phil