Burning Amplifier BA-2 - Page 4 - 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 September 2009, 07:30 PM   #31
The one and only
 
Nelson Pass's Avatar
 
Join Date: Mar 2001
There would be no reason why you couldn't invert the polarity
of the front end, using N channel inputs and a P channel VAS.

If you do so, you will want to find some P channel Mosfets
which don't have the "IR P channel distortion" for best results.

  Reply With Quote
Old 5th September 2009, 05:12 AM   #32
diyAudio Member
 
Join Date: Aug 2008
Quote:
Originally Posted by Nelson Pass View Post
There would be no reason why you couldn't invert the polarity
of the front end, using N channel inputs and a P channel VAS.

If you do so, you will want to find some P channel Mosfets
which don't have the "IR P channel distortion" for best results.

it is possible to use 2sk246 and 2sj103 for the front end?
tqu
  Reply With Quote
Old 5th September 2009, 09:45 AM   #33
Jason is offline Jason  Australia
:)
diyAudio Administrator
 
Jason's Avatar
 
Join Date: Oct 2000
Location: Melbourne
Blog Entries: 1
Default PDF updated

The output stage diagram has been updated. The PDF revision has been updated to Rev 2.0.
  Reply With Quote
Old 6th September 2009, 03:45 AM   #34
diyAudio Member
 
Zero Cool's Avatar
 
Join Date: Sep 2004
Location: MN
Ok so who is working on a group buy for PCB boards? anybody worked out the layout yet?


Zc
  Reply With Quote
Old 6th September 2009, 06:23 AM   #35
Variac is offline Variac  United States
diyAudio Editor
 
Variac's Avatar
 
Join Date: Dec 2001
Location: San Francisco, USA
cviller is working on it again. He has some preliminary designs that he will post very soon, but the concept has changed, which made it more reasonable to wait for hthe BA-2 to be revealed. The idea is to have the gain stage board separate so that it will work for BA-1 and BA-2 with additional different small bias boards for the two types of amps That way, with one board we can make both types of amps and/or have an external gain stage. It will be posted here in a few days. Nelson intended this to be a fundraiser for diyAudio so we want to be the only ones making the boards, but we realize that a responsibility goes with that- moving ahead!

Shortly we will have a design for your comments and input, then a Group Buy listed in the wiki and the GB areas..

Of course the hope is that many more people make these amps than the few that got amp chassis at BAF

Mark
-Variac
  Reply With Quote
Old 6th September 2009, 09:33 AM   #36
diyAudio Member
 
chinsettawong's Avatar
 
Join Date: Jun 2006
If a group buy for PCBs will be available, I think it will be a good idea to also make a group buy for matched Mosfets and Jfets as well.

Wachara C.
  Reply With Quote
Old 6th September 2009, 01:34 PM   #37
diyAudio Member
 
Zero Cool's Avatar
 
Join Date: Sep 2004
Location: MN
Oh good i was hoping the front end would be a separate board!

A group buy for the jfets would be nice!
  Reply With Quote
Old 6th September 2009, 07:33 PM   #38
cviller is offline cviller  Denmark
diyAudio Member
 
cviller's Avatar
 
Join Date: Dec 2005
Location: Copenhagen
Blog Entries: 2
Quote:
Originally Posted by Variac View Post
cviller is working on it again. He has some preliminary designs that he will post very soon, but the concept has changed, which made it more reasonable to wait for hthe BA-2 to be revealed. The idea is to have the gain stage board separate so that it will work for BA-1 and BA-2 with additional different small bias boards for the two types of amps That way, with one board we can make both types of amps and/or have an external gain stage. It will be posted here in a few days. Nelson intended this to be a fundraiser for diyAudio so we want to be the only ones making the boards, but we realize that a responsibility goes with that- moving ahead!

Shortly we will have a design for your comments and input, then a Group Buy listed in the wiki and the GB areas..

Of course the hope is that many more people make these amps than the few that got amp chassis at BAF

Mark
-Variac
I just did a quick layout of the frontend for you guys to comment on. The silk screen is still a bit messy and a few components will be aligned more nicely later. But I would like to get some feedback.

I have attached a blue/red version, where blue is bottom and red is component layer.
The green version gives a better impression of how the boards will look like when produced.
Attached Images
File Type: png frontend_merged.png (22.1 KB, 1899 views)
File Type: png frontend_merged_p.png (48.4 KB, 1898 views)
  Reply With Quote
Old 6th September 2009, 09:50 PM   #39
tms0425 is offline tms0425  United States
diyAudio Member
 
Join Date: Oct 2006
Location: Ft. Wayne, IN
Any chance the large connection pads could be a little bit further apart?

I will use Keystone turret terminals instead of soldering to the board thru hole directly, since they're going to get taken apart and put back together a lot. The larger ones like #1503 have a collar on the top of that is 0.187" (4.8mm) so they get VERY close on the F5 power supply boards I have now.

Tom
  Reply With Quote
Old 7th September 2009, 03:16 AM   #40
cviller is offline cviller  Denmark
diyAudio Member
 
cviller's Avatar
 
Join Date: Dec 2005
Location: Copenhagen
Blog Entries: 2
Quote:
Originally Posted by tms0425 View Post
Any chance the large connection pads could be a little bit further apart?

I will use Keystone turret terminals instead of soldering to the board thru hole directly, since they're going to get taken apart and put back together a lot. The larger ones like #1503 have a collar on the top of that is 0.187" (4.8mm) so they get VERY close on the F5 power supply boards I have now.

Tom
Hmm.. I have to think about that. The reason for the distance (~5mm) I have chosen is that it fits with many standard terminals. If you can point me to some reasonably priced easy to get terminals of a different spacing than 5mm, I might change it.

BTW: The board is 2.7x5.4 in inches.
  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
Burning Amplifier BA-2 Nelson Pass diyAudio.com Articles 5 14th September 2011 07:11 PM
The Burning Amp Festival-Burning Gadgets Preview Zen Mod Everything Else 115 27th October 2007 06:50 PM


New To Site? Need Help?

All times are GMT. The time now is 02:32 PM.


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