Pls Help - Sumo Polaris II

A friend tell me, that his device of this model have a more distorted left channel (in opposite to the right channel).
By comparing the fig. 4 and 5 under
Sumo Polaris II power amplifier Measurements | Stereophile.com
there is to see in the diagrams the same as what would be accordingly the description of the listening test.

Occurs this crossover distortion by a design error ?

Who can upload the schematic ?

Maybe similar to the model "NINE PLUS" ?
HIFIDIY-<SUMO>Circlotron - Powered by Discuz!
SUMO "the Nine"

Thank you very much
 
A friend tell me, that his device of this model have a more distorted left channel (in opposite to the right channel).
By comparing the fig. 4 and 5 under
Sumo Polaris II power amplifier Measurements | Stereophile.com
there is to see in the diagrams the same as what would be accordingly the description of the listening test.

Occurs this crossover distortion by a design error ?

Who can upload the schematic ?

Maybe similar to the model "NINE PLUS" ?
HIFIDIY-<SUMO>Circlotron - Powered by Discuz!
SUMO "the Nine"

Thank you very much
My Sumo Polaris has been in almost continuous use for 30 years, and in the last week was giving an awful "graininess" -- notably in vocals (was listening to some Palestrina). Apparently, the distortion adjust is out of whack. Thanks @tief for putting me onto that Stereophile article.
 

Attachments

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The Stereophile article is illuminating in several respects, not the least of which is the shoddy construction. My Sumo upon further examination was missing the transformer screw as cited in the article.
More interesting -- take a look at this picture -- only one of the MOSFETs had any silicon paste -- and the one which did fell off when I removed it from the heatsink!
 

Attachments

  • Sumo Polaris PCB Bottom.jpg
    Sumo Polaris PCB Bottom.jpg
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