Questions to Classé Audio Model Seventy (70) Power Amplifier

[tiefbassuebertr]

First PDF show the schematic diagram of power amp on page 2.
I note, usual topology for the output buffer (usual complementary discrete darlington power follower stage) is in use.
But the first stage of darlington use the same BjT types (Toshiba's 2SA1302/2SC3281) like the output stage (usual for first stage of such discrete darlingtons are e. g. Toshiba's 2SA968/2SC2238).
Is this a misprint or a special future from Classè Audio ?

If it is a special future, what advantage should be achieved (from my view the higher capacitive load represents a disadvantage for the previous cascode VAS) ?
Thank you for an advice.

images are here:
https://www.ukaudiomart.com/details...lasse-audio-seventy-amplifier/images/2959481/
https://www.audiosciencereview.com/...e-itch-again-looking-at-500-1k-dac-amps.6987/

P.S.: this thread don't provide the right information

B

Thread 'Power amp right channel running hot.'

2012-11-02 9:13 pm

I am just putting a Classe Seventy power amp back into service after several years in storage & the right channel is running much hotter than the left. Not running it very hard, so it may be operating in class A, but both channels are equally loud. Around .4v max into 4 ohms.
Since I have an assumed "good" channel, should I compare bias readings between them? I think I have a schematic too. What sort of problem should I be looking for?

Thanks,
kev

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