X0.2 Preamp advice & circuit

[Barry1]

Want to know which diy preamp design is most similar to the X0.2 and where schematics might be available

Also looking to modify the the input and output coupling caps on an X0.2 and they don't look the same as the X1

In an earlier post Mr. Pass offered this on the X1:

>>There are film input capacitors (1 or 2 uF depending on the rev #) and 220 uF + film bypass on the outputs.

You may replace the caps with the parts of your choice, but of
course you bear the consequences of mistakes.

As the to 220 uF output caps, we are currently favoring the Elna
Silk capacitors, of which there is an inexpensive 220 uF at 16V
available. >>

Values anyone?


Thanks very much!!! Barry

 

[ANADIGIT]

X0.2 board

I don't have its schematic but I own only its control + suplly + audio board.
Very huge PCB which I never seen before !

I bought from my friend in Spain.

Thanks
Anadigit

 

[ANADIGIT]

Now I try to search a good 10uF or 20uF for Pass X0.2 PCB, does anyone suggest me ?

Thanks
Anadigit

 

[Kovax]

Simmilar to X0.2 you say?

Want to know which diy preamp design is most similar to the X0.2 and where schematics might be available

Also looking to modify the the input and output coupling caps on an X0.2 and they don't look the same as the X1

In an earlier post Mr. Pass offered this on the X1:

>>There are film input capacitors (1 or 2 uF depending on the rev #) and 220 uF + film bypass on the outputs.

You may replace the caps with the parts of your choice, but of
course you bear the consequences of mistakes.

As the to 220 uF output caps, we are currently favoring the Elna
Silk capacitors, of which there is an inexpensive 220 uF at 16V
available. >>

Values anyone?


Thanks very much!!! Barry

Well, you can try this ...

http://choky.diyaudio.rs/downloads/The Pumpkin & Shunty.pdf

and the thread is here ...

http://www.diyaudio.com/forums/pass-labs/119070-pumpkin-preamp-more-boring-making-thread.html

Highly regarded design thx to Zen Mod.

 

[generg]

Try it

🙂 Zen Mods Pumpkin can be driven with no input caps and with 10uF at the output.😀

It is my favorite pre and it is constructed very close to X0.🙂

 

[ANADIGIT]

I saw too many different between X0.2 & Pumpkin but there're no problem I need only any advice for 10uF CAP, Where can I find AEON CAP ?
X0.2 used additional gain stage above Pumpkin and used X-CIRCUIT only buffer stage not suitable for gain stage !

Thanks
Anadigit

 

[Kovax]

I hate to do this but ...

I saw too many different between X0.2 & Pumpkin but there're no problem I need only any advice for 10uF CAP, Where can I find AEON CAP ?
X0.2 used additional gain stage above Pumpkin and used X-CIRCUIT only buffer stage not suitable for gain stage !

Thanks
Anadigit

Read this pls ... then google is u best friend ...

http://www.diyaudio.com/forums/pass-labs/90030-coupling-caps-aleph-ono-xono-aleph-x0.html

 

[ANADIGIT]

Some circuit

I found some schematic from google search.
Could anyone have a correct point ?

Thanks
Anadigit

 

[ANADIGIT]

Controller

Semi completed preamp.

66 Steps attenuator.
6 Inputs and 2 Outputs.
30 second muting.
Stereo/Mono
Balance/Single End

Next step I'll change 7-Segment display to VFD Display.

Thanks
Anadigit

 

[generg]

I saw it at the Chinese DIY community......

A bit too complicated for me, the attenuation circuit must be really good, one of the treasures of Nelson.

You do not forget that the circuit is still not given free by Nelson?

 

[ANADIGIT]

I don't have any schematic onhand.
I applied it from top overlay print screened only 🙂

Thanks
Anadigit

 

[generg]

yes I did the same..... and saw the great similarity to the original X0 concerning the core of the circuit.

 

[ANADIGIT]

But I think origina Pass used a great matched and better quality more than me 🙂

It's my hobby about HIFI
I have a better preamp (Burmester) for DIY

Thanks
Anadigit

 

[wintermute]

Hi Anadigit, did you find your axon (note the spelling) caps? although they don't stock the 10 uF size, partsconnexion has 11uF axons for $2.88 US each. AXON True Cap Metallized Polypropylene Capacitors

Tony.

 

[ANADIGIT]

AEON

Hi Anadigit, did you find your axon (note the spelling) caps? although they don't stock the 10 uF size, partsconnexion has 11uF axons for $2.88 US each. AXON True Cap Metallized Polypropylene Capacitors

Tony.

Hi,
No, I still finding 10uF AEON from US supply. Now I have some problem about 2SK389 from China supplier I think it was remarked from someone whom want to get my bullet 😡

When I test original 2SK389BL from Borbely Audio I got 12mA but when I change to Chinese 2SK389BL (look like new screened) I got over 30mA !!!

If i have a time enough for DIY I'll cut a circuit of X-buffer to Pumpkin Preamp 🙂

Thanks
Anadigit

 

[ANADIGIT]

Semi complete !

These're my semi complete preamp, I used 20uF AEON and 10uF Panasonic.
Goal of this preamp is Unbalance Output because it's hard to select matched resistor and current LED for CCS control. I prgram Atmega MCU only volume and selector control also display shut down function. I can't find hard to obtain 20*1 VFD display as original designed.

Thanks
Anadigit

 

[ANADIGIT]

VFD display

Now I try to change 7-segment to 20x1 VFD display. it's almost completed 🙂
I bought this display from OEM factory of NAD S500 cd player display as spare parts.

I have many idea to use them and apply to other function of input/output and volume control.

 

[generg]

analog_guy said the same.....

 

[ANADIGIT]

analog_guy said the same.....

Yes, you said the same to him, too

 

[generg]

hi, hi good to have same sources...