My design L20D IRS2092+IRFI4020H 200W8R

Peytr, there are many times more class D amps in the world than in all the other classes put together. Every modern TV, mobile phone, most car stereos produced now use class D.

I used some early Sony Class D amps in the 80s and there were unreliable but the technology is mature and if sourced from reputable manufacturers, extremely reliable.
 
Its ok if you have plenty of time fixing them, and you have technical experience but these Chinese copies are unreliable because they are cheap and the parts are sub standard(fake) but hey its ok if you like it but for me I am sick of the fake parts and also D amps are fussy if you don't design them carefully, but when they have worked for me they sounded really amazing until they just stopped working, there are lots of pages nobody wants to admit they made a mistake, I'm sorry if I am negative but I haven't had much luck building them, but class A or A/b no worries.
 
My experience with L15-20-25D and Sure 2x250/8 is quite different. No big problems have I ever had with them.

And you can also find lots of pages regarding A/AB amps where diyers ask for help and assistance.

I understand, it's hard to imagine that cheap Chinese amplifiers would play music as well or even better than expensive good-old-ones from the past.

In my house - they do. :)
 
I checked the Toroidy.pl transformer and it's their audiograde 500VA 0-48VAC 0-48VAC version.
That should give me about +/-68Vdc after rectification.
So it should work well with the L20D modules.

I'm thinking that a C-R-C or C-R-C-R-C filter may drop the voltage from the standard (48×1.42) to somewhere between +/-65V to +/-67V.
IIRC I have 6pcs 4700uF/100V Epcos capacitors.
 
L15D (modded) measurements, 1W 10W 47W into 4R
linear unregulated psu +-48V
 

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