[staatlich geprüfter Preamp tester!]

Auf Seite 1 der Plan der mir am Wochenende begegnet ist  :laugh:
Mir fiel sofort der Slope R von 39k auf, wenn ich mich nicht irre ist das
Olafs Lieblingswert, weil er ein zwischending  von 33k und 47k (original) ist


Ich war so frei den Widerstandswert am Gitter von 47k auf 470k zu erhöhen (Blatt 2)

Auf Seite 1 der Plan der mir am Wochenende begegnet ist  :laugh:
Mir fiel sofort der Slope R von 39k auf, wenn ich mich nicht irre ist das
Olafs Lieblingswert, weil er ein zwischending  von 33k und 47k (original) ist


Ich war so frei den Widerstandswert am Gitter von 47k auf 470k zu erhöhen (Blatt 2)

Sorry for reopen this old thread but I'm gonna mod my studio pre converting it to cae 3+ crunch channel...
Searching for a schematic is a mess! so many versions! Can I ask you what is the difference between page 1 and 2 of the last posted schematics? thank you very much...

Hi, there are some different values for capacitors and the first tube also a different circuit.

lg
Kai

yes but what is supposed to be the correct one?
assuming both schematics come from the same 3+ preamp...
From another thread of Dr. Nöres who actually built it seemed there were some errors in that schematics...
I couldn't understand very much due to my total ignorance in german...
Do you followed that thread?

Han die Blume?

Hi, I don't know which one is the original. I would rather chosse the one which suites my needs better.
lg
Kai

I fully agree with Kai. Just take one of the schems as starting point, build it and listen. Then tweak until it sounds good to you. If it finally does there is no need to care whether it matches the original by 100%.

Cheers Stephan

My approach is the same! I actually don't care what resemble better the original but from what I understood of the cae3+ thread there were actually errors (not just copy error) like wrong rc filters values... Do I explained myself? A little bit maybe?

You explained yourself well but honestly I don't know whether one, both or none of the schems are correct since I have never looked inside an actual CAE amp. The schems could show different versions of the same amp since manufacturers make changes without giving notice to the public.

Cheers Stephan

thank you very much darkbluemurder!
however the thread I'm referring to is that one: http://www.tube-town.de/ttforum/index.php?topic=4149.msg54588#msg54588
that link will get you at page 22 where I think Nöres and Sebastian speak about these errors... It is my guess because as I said I don't know german at all unfortunately...
If you have one or maybe two spare minutes could you look at that link? probably you could understand what errors they're referring to in a bunch of seconds...
thank you in advance...

In post #305 of the linked thread Dr. Nöres explains that the grid stopper before V4a is a 475k (470k), not a 47k as indicated in one of the schems and as he used. That was the source to his metallic sound problem since a 470k before the grid would roll off more highs due to the miller capacity.

He also mentions that the cathode resistor of that gain stage is a 10k, not a 15k.

In post #311 he explains that he changed some of the resistors in the B+ line to increase the voltages.

Hope that helps.

Cheers Stephan

Really thank you darkbluemurder!!!:)