2stageEF high performance class AB power amp / 200W8R / 400W4R

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Prepare transistors legs, insert into pcb. mount it on heatsink. screw the transistors without thermal pads. cut the transistor pins. remove screws , transistors. insert and solder lytics. insert transistors into pcb, mount it on heatsink, carefully solder the transistors with a small/long solder iron.

HNY2024
 
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Heureka, first setup okay, seems to have worked without error.

DC (+20V, -20V) Current consumption: 53mA
DC offset: 50mV

I'm happy...
 

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Today I finally got around to actually running SA2014 and hooked up the speaker. I'm satisfied with the sound overall, the SA2014 was only connected to a smartphone and a DC 43V power supply. I am waiting for the 600W toroids from toroidy.pl to arrive so I can complete the bias and start work on the second channel.

No bumps in the speaker when turned on or off.
Have a nice Saturday :)

 
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The first 600W transformer from toroidy.pl at home (240V, 2x50V). First channel finally done, bias set to 21.3 mV, supply voltage at idle 69.2V, DC offset 4mV. Hopefully in March I'll get to finish the second channel. I'd like to have SA2014 in the box finished by the end of the year!
 

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Tony,
I have a question! I am now also choosing a preamplifier for the SA2014 and I want it to be from discret parts (no operational amplifiers) and at the same time not too complicated. So far the Sapphire from RJM seems to be a good candidate. Since I want to set it to Class A, how much input sensitivity does the SA2014 have at full power?

If I calculate correctly it comes out to about 1.3V