MPP

[Onvinyl]

I can see no obvious errors, but maybe those 14k Resistors need to be tweaked a bit.

Those Salas style shunts are not easy to get right. I tried several similar circuits of my own, but Salas' where the only one to work stable and without small or tall oscillations, but layout is a major issue (at least in p2p-breadboard).

PM sent.

Rüdiger

 

[mad_z]

...I have a fine Macbook Pro now but i swear that my IBook was the next day in Poland giving maybe 100,-€ on the black market.
It´s pathetic, those pricks really suffer a bad life.

I would not count on Poland Joachim. We are far worse thieves than most of German people belive + we really can afford laptop or PC without much hassle...

Please PM me, maybe macbook is still trackable.

Marcin.

 

[Joachim Gerhard]

Sorry about accusing your people, that was just a place holder. But is has happened to a friend of mine that had his fashion shop robbed twice. His stuff appeared is east europe shortly after. He had to close. Those guys also stole his transporter, drove to the Autobahn, dropped it there and stole another car to continue the journey. That way they where impossible to track. Thanks for offering help.

 

[RCruz]

After extended Listening sessions we have found out that painting the top of the transistors with this nail laquer (PRITI NYC MINI Nagellack - keepsake rose - Zalando.de) gives a better resolution in the higer mids.

Maybe caused by the additionel damping.



Sam

Hi Sam

Maybe I should go for it now as there seems to be a discount

 

[masag1]

Hi Sam

Maybe I should go for it now as there seems to be a discount

That was good Recardo

Regards

 

[Benedetto]

As promised before;
HB's Shunty

 

[Joachim Gerhard]

Thanks.

 

[Onvinyl]

That was at a time where i had illusions about offset in transimpedance stages. This thing needs a servo but i could not even make the bias work in the input stage so i stopped there.

Joachim, in my desing on post 2056 I had to parallel some of the 86R-Resistors of the current mirrors to null the (otherwise enormous) offset. The bias remains stable since.
No servo needed.

Rüdiger

 

[hesener]

tried the "paradise lost" shunt reg with a mosfet CCS, works beautifully. the advantage over the LM317 CCS is that the dropout voltage can go down to 1v whereas the 317 requires at least 4v to work ok , and its not a lot more components... credit due to ikoflexer for this ccs...

 

[Onvinyl]

a mosfet CCS should have a higher bandwith as well, doesn't it?

Joachim, where do you source the common mode chokes from?

Rüdiger

 

[Bksabath]

chokes

why not Gyrators?

 

[Joachim Gerhard]

Yes, that is also what i would try. The LM317 is also no good over 10kHz. One could also cascode the LM317 with another LM317 ( aka Walt Jung ) for a big improvement but then we drop over 6V. Has anybody the patients to modify the JHW ( Joachim, Holger, Werner ) that way? I think you, Hesener have done that already so may i ask for a contribution ?
Rüdiger, i check that out.

 

[FdW]

After extended Listening sessions we have found out that painting the top of the transistors with this nail laquer (PRITI NYC MINI Nagellack - keepsake rose - Zalando.de) gives a better resolution in the higer mids.

Maybe caused by the additionel damping.



Sam

Did you also try other colors? And brands? And are those animal tested or mannequins only? And where the listeners blind or double blind?

 

[Joachim Gerhard]

I buy the Talemas at Reichelt. They cost around 1.5€. I was critizized for using ferrite cores on this thread so some Panasonic where suggested. You get them at Digikey.
I have to go back on this thread for the exact model. There are horizontal and vertical mounted versions. I thing they are from series 400 but i have to double check that.

 

[Joachim Gerhard]

Here you find Walt Jung´s work about current sources. There is also a Mosfet-LM317 cascode.

 

[Joachim Gerhard]

Rüdiger, with a load of only 10kOhm DC stability is much better but the MPP that i have scanned here has a DC impedance of over 10 x as much so offset goes up with this.

 

[Joachim Gerhard]

Sorry, here is the Link to Walt Jung...
Services

 

[Joachim Gerhard]

Here is a Panasonic choke that has some credibility.
Digi-Key - PLK1078-ND (Hersteller - ELF-18N004A)
On that page there are links to other variants too.

 

[RCruz]

Sorry, here is the Link to Walt Jung...
Services

Nice rading .. Thank you.

 

[Onvinyl]

Regarding to bias.
I remember that I selected the CM-Q's for Hfe for each polarity (with a DVM, so probably not that effective). I did not manage to select equal Hfe between p and n, they were too different, though.

Rüdiger