Experimental Design - Comments, Flames Welcome - 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 29th May 2002, 01:07 AM   #1
diyAudio Member
 
Join Date: May 2001
Blog Entries: 5
Default Experimental Design - Comments, Flames Welcome

First, to the uninitiated: please don't build this circuit. It is only a conceptual schematic. I'd really like to hear the thoughts of your group and, if he would do me the honor, the "Big Guy" (NP)! Particularly, I'd like to figure out if there's a simple way to employ mosfets in the OP.

Thanks

Mike
Attached Files
File Type: zip classa.zip (3.5 KB, 1760 views)
  Reply With Quote
Old 29th May 2002, 03:53 AM   #2
diyAudio Member
 
Join Date: May 2001
Blog Entries: 5
Default MOSFET version

Here's the mosfet version almost ready for alligator clips and duct tape!
Attached Files
File Type: zip mosfeta.zip (4.7 KB, 1442 views)
  Reply With Quote
Old 29th May 2002, 08:22 PM   #3
The one and only
 
Nelson Pass's Avatar
 
Join Date: Mar 2001
OK. but I have to think about it for a while.
  Reply With Quote
Old 30th May 2002, 05:45 PM   #4
diyAudio Member
 
Join Date: May 2001
Blog Entries: 5
Excellent! Thanks Mr. Pass!
  Reply With Quote
Old 30th May 2002, 06:31 PM   #5
diyAudio Member
 
Join Date: Feb 2001
Location: Columbia, SC
I glanced at if briefly. Need to get back to painting walls, etc. My first impression is: Circlotron.
If so, bear in mind that that output stage is patented by Ralph Karsten.
I'll try to look at it in more detail later.

Grey
  Reply With Quote
Old 31st May 2002, 09:14 AM   #6
diyAudio Member
 
Join Date: Dec 2000
Location: Germany
Default Circlotron

Yes Circlotron,
I donīt kwow the content of the Ralph Karsten patent, but there are many Circlotron amplifiers out there: Einstein OTL, Audio Valve and every power amplifier from Balanced Audio Technology,
tube and transistor.

Reinhard from Germany
  Reply With Quote
Old 31st May 2002, 03:42 PM   #7
diyAudio Member
 
Join Date: May 2001
Blog Entries: 5
Grey, Reinhard:

Thanks for your replies. Yes, I would say the OP qualifies as a circlotron. It does remind me of an old OTL tube schematic I saw in TAA. I had a look at the Karsten patent and I don't believe this circuit is is directly comparable. To my unqualified eye it is just a balanced bridge with batteries in two of the arms. In fact, the inspiration for the OP came from a 1960's U.S. Navy transistor book. I was originally trying to work-up something along the lines of a two stage "Son of Zen" and this where I ended up. I'm working on a currnet flow diagram to help clarify the circuit action in my mind. It is problematic at the moment, and I haven't figured out a good way to apply overall feedback. I wonder if th "X" feedback topology would work? Also I think I see an easy way to dynamically bias the OP, but it'll have to wait for the weekend. I really appreciate your comments. Please keep them coming.

Mike
  Reply With Quote
Old 31st May 2002, 04:35 PM   #8
diyAudio Member
 
Join Date: May 2001
Blog Entries: 5
If I may go off topic for just a moment, I've been wanting to thank Nelson Pass for a decade or so. I built the A40 when I was in the Army, stationed in Germany, and I've been having fun with this hobby ever since, due mainly to the generous contributions of Mr. Pass. It is a terrific hobby.

Have a great vacation.

Mike
  Reply With Quote
Old 31st May 2002, 05:17 PM   #9
diyAudio Member
 
Join Date: Feb 2001
Location: Columbia, SC
I still haven't had time to go back over the circuit but, to the extent that it is (maybe) a Circlotron, yes, X will work. Keep an eye on the phase and all will be well.

Grey
  Reply With Quote
Old 1st June 2002, 10:19 AM   #10
djk is offline djk
diyAudio Member
 
djk's Avatar
 
Join Date: Feb 2001
Location: USA
X100 backengineered here
Each half of the bridge acts like a current source for the other.Only one polarity output device needed.A 50W amp could be made from one pair of IRFP22N50A ,a 277W device available from DigiKey for $2.45 .Since no devices are paralleled no matching should be needed.If you have trouble visualizing this just draw it out on a sheet of paper.Prior art shows both tube (Atamasphere) and BJT (Sumo) versions of this idea.
Circlotron
  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
Experimental loudspeaker design -need criticsm BMD Multi-Way 12 15th October 2011 09:55 AM
Any comments on this design? icebear Tubes / Valves 23 19th May 2009 05:07 PM
experimental 6L6G / 6BG6G amp design brainstorm chromal Tubes / Valves 34 21st March 2009 12:45 AM
need comments on amp design metebalci Tubes / Valves 0 10th September 2006 09:03 PM
Best driver for an experimental design BMD Full Range 12 13th May 2006 12:30 AM


New To Site? Need Help?

All times are GMT. The time now is 09:46 AM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright Đ1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2