X0.2 Preamp advice & circuit - diyAudio
Go Back   Home > Forums > Amplifiers > Pass Labs

Pass Labs This forum is dedicated to Pass Labs discussion.

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Reply
 
Thread Tools Search this Thread
Old 4th June 2008, 01:13 AM   #1
Barry1 is offline Barry1  United States
diyAudio Member
 
Join Date: Apr 2007
Default X0.2 Preamp advice & circuit

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
  Reply With Quote
Old 15th January 2011, 04:41 AM   #2
Banned
 
Join Date: Nov 2008
Default 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
Attached Images
File Type: jpg IMG_3995.JPG (160.1 KB, 1353 views)
  Reply With Quote
Old 3rd February 2011, 03:35 AM   #3
Banned
 
Join Date: Nov 2008
Now I try to search a good 10uF or 20uF for Pass X0.2 PCB, does anyone suggest me ?

Thanks
Anadigit
  Reply With Quote
Old 3rd February 2011, 10:03 AM   #4
Kovax is offline Kovax  Croatia
diyAudio Member
 
Join Date: Aug 2002
Location: Zagreb , CROATIA
Default Simmilar to X0.2 you say?

Quote:
Originally Posted by Barry1 View Post
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/T...6%20Shunty.pdf

and the thread is here ...

Pumpkin preamp - More Boring Making Thread

Highly regarded design thx to Zen Mod.
__________________
If it can't be fixed ... use a bigger hammer
  Reply With Quote
Old 3rd February 2011, 10:47 AM   #5
generg is offline generg  Germany
diyAudio Member
 
generg's Avatar
 
Join Date: Jul 2009
Location: Near Frankfurt
Default 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.
__________________
and the First Wtt is......a really First Class PSS Idea
  Reply With Quote
Old 3rd February 2011, 11:23 AM   #6
Banned
 
Join Date: Nov 2008
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
  Reply With Quote
Old 4th February 2011, 04:28 PM   #7
Kovax is offline Kovax  Croatia
diyAudio Member
 
Join Date: Aug 2002
Location: Zagreb , CROATIA
Default I hate to do this but ...

Quote:
Originally Posted by ANADIGIT View Post
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 ...

Coupling Caps in Aleph Ono/XOno and Aleph X0
__________________
If it can't be fixed ... use a bigger hammer
  Reply With Quote
Old 6th March 2011, 04:01 AM   #8
Banned
 
Join Date: Nov 2008
Default Some circuit

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

Thanks
Anadigit
Attached Images
File Type: jpg x02sch.jpg (108.1 KB, 864 views)
File Type: jpg x02schrca.jpg (29.4 KB, 813 views)
  Reply With Quote
Old 13th April 2011, 09:48 AM   #9
Banned
 
Join Date: Nov 2008
Default 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
Attached Images
File Type: jpg Pass X0.2 completed.JPG (76.2 KB, 683 views)

Last edited by ANADIGIT; 13th April 2011 at 09:50 AM. Reason: I love you
  Reply With Quote
Old 13th April 2011, 09:59 AM   #10
generg is offline generg  Germany
diyAudio Member
 
generg's Avatar
 
Join Date: Jul 2009
Location: Near Frankfurt
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?
__________________
and the First Wtt is......a really First Class PSS Idea
  Reply With Quote

Reply


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Major amp circuit redesign- need some expert advice ambience exists Tubes / Valves 6 13th June 2009 09:16 PM
X1 preamplifier circuit advice AD Pass Labs 7 18th April 2008 05:08 PM
Problem in an Encoder circuit design. Pls advice.. xitronics Parts 4 19th July 2005 03:14 PM
AV Preamp advice... eRiCdWoNg Everything Else 0 9th January 2004 03:46 AM
Nees advice on preamp psu. JoeBob Solid State 3 13th December 2002 01:22 PM


New To Site? Need Help?

All times are GMT. The time now is 12:35 AM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright 1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2