Current feedback Mosfet Circlotron

[UltimateX86]

Current feedback Mosfet Circlotron : it's alive !

Hi,

I present you the amp that I just realized.

This is a current feedback Mosfet Circlotron

Without Diyaudio forum and another French, this amp could never be created.

So thank you all the people who helped me and especially Joe Berry who gave me the Keystone of this amp, the current generator so particular that guarantee a thermal stability

A special thanks to gionag, my friend Rabbi Michele, who is the first to have made this amp and who made this great layout


YouTube : low cost phone record... but it's alive !

in real R15=500, R14=220, C3-C4= 47p

YouTube : low cost phone record... but it's alive !

 

[Joe Berry]

Congratulations!

Subscribed.

 

[jpatay]

Perfectly!!!:
I will also assemble this circuit.

 

[UltimateX86]

Bom example

gionag made a simpler version, without stack, but not tested

gerber on request

 

[U130421]

This amp needs to be driven by a differential source . How do you supply it? an input transformer may be ?

 

[UltimateX86]

it could work in asym but performance is worse, I use a symmetrical DAC on youtube video, but I can use a UGS preamp or a transformer (LL1690)

UGS adventures

 

[gionag]

this amp deserve a listen. good job seb.
can be a start for a long discovery journey.

 

[moschfet]

I am glad to see that you have managed to build your circlotron.

 

[UltimateX86]

Merci

 

[Yurik_V]

UltimateX86, сongratulations on your new design! An interesting amplifier. Did you measure the parameters of this amplifier?

moschfet. Built your circlotron, so far only one channel. But I’ll do the second channel too. Good parameters and thermal stability.

 

[UltimateX86]

For the moment I do not have the material yet to take measurements but I will invert soon

However Michele did an arta but it seems to me that it was not in optimal conditions

 

[analog_sa]

Wow, a great presentation! Is it possible to share the asc file?

 

[Yurik_V]

Wonderful! THD below -100dB. I hope to repeat your amplifier in the near future.
In my Patrick's amplifier, the parameters turned out a little worse. But in my version, the power of the pre-amplifier should be less so far.

 

[moschfet]

UltimateX86, сongratulations on your new design! An interesting amplifier. Did you measure the parameters of this amplifier?

moschfet. Built your circlotron, so far only one channel. But I’ll do the second channel too. Good parameters and thermal stability.

Hi Yurik, nice to see, that my circuit work and have children

I have to admit that I'm a little jealous when I see Ulti's spects

 

[UltimateX86]

Wow, a great presentation! Is it possible to share the asc file?

here it is, but change the TTA model for 2SA1360 or 2SA1381

the model is completely smoked

So in real amp we could lower the compensation, and the amp could work with these transistors too

 

[Yurik_V]

UltimateX86, I have a question: capacitors C3, C4 are connected in different ways on the diagram and on the printed circuit board. Which option is correct?

 

[gionag]

UltimateX86, I have a question: capacitors C3, C4 are connected in different ways on the diagram and on the printed circuit board. Which option is correct?

you are totally right...
my bad... i have placed the component in the wrong position.
the one in the simulation is correct.
i will update the pcb very soon

 

[Yurik_V]

OK thanks.
There's a esch several inconsistencies between the circuit and the PCB.

 

[gionag]

... really ? can you point me out where you have discovered the discrepancies ?

thanks

 

[Yurik_V]

Maybe I'm wrong, but now I’ll clarify. I’ll inform you soon.