F5 power amplifier

I did some listening test on channel that works.
I can say I prefer the Mepco capacitors over the Mallory.
The sound became too smooth (not bad but somehow, something missing) and the dynamics (attack) also became a bit less.
It became a bit too smooth to my taste (!) of course this capacitors are first time in an amplifier (NOS) VS the Mepco I used those over the years for testing. I think I will mix the Mallory with the Mepco, (I have 4PC from both of them) that is my next plan, that way will have two very same PS. Before the PCB I will put the pair Mepco.
Maybe it just need to be break in? I don't know.
One more time not bad but something missing how I heard the amp previously.
Maybe the Zen Mod idea about the Philips poly-carbonate (yellow) caps not always useful?
Ha, ha, ha -, I am kidding Zen.
 
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https://www.diyaudio.com/community/threads/ludef.369990/post-6997306



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Again, Eh, Not that simple

I replaced all the semi conductors, (pull of two miniature eyelet at the J Fets, Fix it under a magnifying glass)
measured all the resistors accept the two 5W type. :mad::mad::cry::cry:
I mounted into the smaller test model set it up all DMM and no bias at all.
Again the same issue.
I pull it a part and now to found out one of the Fukushima R 0.22 5W resistor is open without any burned mark.
I will replace that soon let see, fingers cross.
It is a very simple, little amp giving me so much trouble!
 

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This amplifier runs hot!!
Set up both channel in the bigger enclosure (it supposed to be twice as big heatsinks for this amp).
Total bias between the PCB+ and rail V+ measured 1.1 Amp after 1 hour warm up, without music. Across the 5W 0.22R I measure 236 mV.
Unfortunately I do not have 18V transformer, I got 20-0-20V and that gives me extra 4VDC total 28VDC rail voltage under load under load.
I measured the temperature around the mosfets 50 Celsius without music.
For now I leave it like that, the second channel needs a pot for the signal and ready to use.
I think I will build this amp based on the F5m in the right enclosure like 5Kg heat-sink / channel.
I have 2 matched pair of the bigger Toshiba mosfets and with those. I love the sound so why not.
I also think about the F4 version but I am not sure if that can be driven with most of the pre-amplifiers?
Zen you know that, please let me know. Thank you!
Greetings