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200W Class A Power Amp

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No, the transistors Q1 to Q10 are swapped NPN vs PNP. So I would not build according to this schematic. It looks like a crossbreed between the original cresendo, the mini cresendo and the axl, but like I said with errors.

Perhaps it's better to start with a proven design and learn from this. I build my cresendo many years ago, and had quite trouble to get is osculation free.
May I suggest to take a look at ESP Projects Pages - DIY Audio and Electronics.
Lots of usefull information at that site.

I will not burn my fingers on the discussion between class A and AB (this design). In principle class a is better, but there are many constraints. Power output is most of the times much lower due to heat dissipation. Learn and make up your mind.
 
litter bit depend on bias adj

No, ClassAB, inverting amplifier.

Unusual input topology.
Don't like R22 & 23.
I'm not familiar with the Q9 & 10 arrangement.
The PSU seems to have been swapped, or is it the input stage that is swapped?
i dont know why they post wrong some pin of trans. on this circuit.
everything is the same other amp only change Q1,2,3,4,9 by Q5,6,7,8,10.
too many way for build up AMP class A. need check by oscilocope we will know exactly which class will have
 
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