At 100k output impedance, if you connect it to a power amplifier with a cable
whose capacitance is as little as 100pF, the
response will be 3dB down at 15kHz. This is most definitely NOT a competently
designed amplifier.

Speaking in general and not about this product, You could make a case for 100k
out of a preamp into 1Meg on the tube amp side. The case you would make
(assuming short cables) is that you could then use a superior output cap of
smaller value and retain bass response. This is what I do - I use ten Russian
teflon .1 caps together to make 1uF. The teflon caps are so superior to others
I've used that I don't mind adjusting the rest of the parameters. This is
purely DIY, of course, and you wouldn't design this in a production model -
just as you say - because of system matching. But there is a theoretical side.

=== Andy Evans ===
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