Opened it, interested in what I would find, and was quite disappointed.
Following the new trend, they only design a preamp, and fit a ready made power amp and supply whose circuit not even they know.
Or care.
Welcome to the disposable-landfill generation.
They even say so in so many words, and guess it not only means the Power Amp but also some Preamp section:
There are cases that the circuit diagrams are omitted. This omission will
happen to the highly integrated digital circuit boards (e.g. Main Board etc) that
are virtually impossible to repair nor analyze.
I feel like a buggy cart builder around 1906 or so.
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