Luminaria?

[Michael Rothacher]

When I get back home. I'll see what I have. I don't think the step generator on my Tek goes high (low) enough to get what you want.

 

[Dennis Hui]

A resistor will do fine for the low current stuff.

Thanks Mike.

Dennis

 

[wengtech]

i think this little "transistor" doesn't exist at the article schematics.🙄

what is the purpose of this transistors?

thanks.

 

[cwtim01]

This is the DN2540 depletion MOSFET, as buffer.

 

[wengtech]

I see... DN2540(N3)

So I must be bought the wrong type of DN2540(N5)
which is to-220 case.
Can I use this N5 in place of N3 type?

Thanks.

 

[cwtim01]

I used the TO-220 version also in my own build and it worked fine, and you need to be aware that the pin-outs are different.

 

[gadut]

this different approach seems interesting, replace buffer transistor with tube

DIY audio: Tube Buffer SIT Preamp

 

[wengtech]

I used the TO-220 version also in my own build and it worked fine, and you need to be aware that the pin-outs are different.

So I think I'm ready to build one.
Thanks for your info.

this different approach seems interesting, replace buffer transistor with tube

Yes that would be interesting.
But I will try the original taste first.

 

[Michael Rothacher]

Here's a little secret: I chose that particular topology on the buffer so I could try a 2SK79 in that spot, but knowing there weren't many available for diy, I made it so the depletion MOSFET would work just by changing resistor values. And that's why the odd choice, and not the garden variety 2SK170 circuit.

Now you know...the rest of the story.

🙂

 

[generg]

my secret, I have four SK79 in my basement….waiting for a good use!

 

[dady]

Hi Gerd you are retired my man....

 

[generg]

and that means……. ?

🙂)

 

[dady]

.....Nothing....😀
Come on, show us what is possible with the 79s...
I have ten units...waiting for a good idea.




PD
Juan Antonio is amazed with the sound of the last pushpull....
I waiting for finish my CSX ring one for afford the pushpull.

 

[cwtim01]

I should stock some 2SK79 when someone was selling them in the swap meet some months ago, his stuffs seem genuine.

Probably time to search them in Japan ... 🙂

 

[dady]

We got from Japan.

 

[Soundhappy]

Hi Diy Friends


http://www.intactaudio.com/module.html

I am curious about autoformer volume control to skip off all active devices in preamplifier for minimalistic audio signal path so maybe no need more rare vfets. What yours opinions...ok you have them so build Luminaria with 🙂

http://www.enjoythemusic.com/diy/0611/slagle_autoformer_volume_control_modules.htm

 

[dady]

I guess is a solution for a problem that not exist.
My humble opinion frenchie friend....

 

[Soundhappy]

I guess is a solution for a problem that not exist.
My humble opinion frenchie friend....

I have ready lot of gain from CD player ...
yes i can use phono section with SRPP Anzai preamplifier for music on vinyls but that is other story....
With balanced DAC and balanced input vfet amplifier for example CSX1 i can take off jfet buffer and lot mechanical imperfection in disc mouvement and all motor noise from CD player. I say other solution 🙂

 

[nicoch58]

that autoformer volume is one of the best sounding around....

 

[massimo]

my secret, I have four SK79 in my basement….waiting for a good use!

...and you're not alone! 😉
Bought in Japan many yrs ago, a matched quad 9.8mA