high performance 25W PowerAmp

@wahab,
What do you think about this project, the idea and the offer? Are you on board?


kind regards,
HBt.

From time to time i throw a look to check the work in progress, and if i can give an advice it is to replace the OS dual pair + drivers by a single BDV64/65 darlington pair, it s as fast as the BD203/204 + BD235/236 configuration and it hold theorically 125W TDP per transistor, of course some Sanken darlingtons would be much better but they are not cheap, not counting that some of their best parts were obsoleted for some reasons.

The two CCS for the diamond buffer should be set at something like 5-6mA at least even if you keep the OS as it is.

Last but no least a dual differential IPS is by far a better solution than the quite original one, with some care you can approach
the perfs of a classic blameless with the advantage of a true symmetrical driving stage that work flawlessly.

Anyway good luck with the remaining efforts and keep on the good work.

Greetings.
 
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Just a quick thought:
shouldn't it be quite sufficient if the base-base resistor shown in principle with its 8k85 ohms consists of a small compensating network with an NTC?

Just a first thought to resume the project 25W-Krill.
 
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"High performing" is at best a statement regarding some visual measurements, which, however, are irrelevant to audio.

"plays in my home, on my loudspeakers."
What is your home, your loudspeakers?
Why was this user banned? Their combination of utter cluelessness and inflated and ego is hilarious! I’ve been chuckling over this thread all morning.
 
"Ein KRILL kommt selten alleine ;-)"

A big thank you Morten, the postman has just surprised me with a letter from Norway - I'm delighted and will get to work straight away. Putting components together, assembling, soldering ... Work on heat sinks, measure ... happy with an interesting power amplifier! I firmly believe that Steve D. knew exactly what he was doing.

Wow,
I don't know what to say. The first photos will follow shortly.



greetings to you,
HBt.
 
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@m0rten

My work account is slowly filling up ... and cannot yet foresee when I will be able to submit the first data (measurements or descriptions).
D1, 2 & 3 I put it on the soldering/back side, let's see how the thermal tracking turns out - in close contact to the heatsink.

BD203 & 204
must be sufficient for 25 watts for the time being.

We will see
:umbrella:
HBt.
 

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Photostory

The next round is about to begin, but first Beelzebub has to give up his wings. Does the LM385Z work correctly with the Fb pin open? For Morten this time with screw terminals - although I don't like them in an audio amplifier.

The tension rises again immeasurably.
 

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