Gain of line preamplifier

"Variable output impedance is heavy disadvantage of any passive preamp even if you have substantially high input impedance of your amplifier."

Please give your reasons why (using laws of electronics)

1: If using a low (<100ohms) source impedance (which most are).

2: Into a 10kohm passive pot with 1mt of low capacitance interconnect (which most good ones are).

3: Into a power amp with 47kohm or higher input impedance (which most are)

"Nelson Pass would also agree with me."

Your assuming a lot with this bold statement, quoting words that Nelson Pass has never made. In which he's been quoted to say the opposite 6 posts back.

Cheers George

George,
I've never quoted Nelson Pass. If 1,2,3 are true, than probably it's a world of dreams. In the real world it's all vary, but far not "most good ones".

"Nelson Pass would also agree with me"

If that's not putting words into Nelson mouth, I don't know what is.

Cheers George

Like I asked, show the electronic math?

And then post a link to a "quality" interconnect that has high capacitance more than 200pf per foot. And I'll show you a rubbish interconnect?
Because it will create HF filter with tube preamps as well as passive pre's. And the HF audio band filter that it creates is detectable with just listening let alone using math or bench tests.

Cheers George

all i stated that unity-gain preamps have advantages of both: transparency of passive and control of active regardless of wires and input/output impedance matching.