Active current source - diyAudio
Go Back   Home > Forums > Amplifiers > Solid State

Solid State Talk all about solid state amplification.

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 December 2006, 07:03 AM   #1
Nixie is offline Nixie  Canada
Banned
 
Join Date: Jan 2006
Location: Vancouver, BC
Default Active current source

http://www.tubecad.com/2006/12/blog0088.htm
Doesn't that active current source seem pretty similar to Pass' Aleph patent?
  Reply With Quote
Old 4th December 2006, 07:36 AM   #2
Electrons are yellow and more is better!
diyAudio Member
 
peranders's Avatar
 
Join Date: Apr 2002
Location: Göteborg, Sweden
Blog Entries: 4
The current source looks very basic to me. How does Mr. Pass' current source look like?
__________________
/Per-Anders (my first name) or P-A as my friends call me
  Reply With Quote
Old 4th December 2006, 01:10 PM   #3
Nixie is offline Nixie  Canada
Banned
 
Join Date: Jan 2006
Location: Vancouver, BC
I'm talking about this one: "the current varies with the output swing, drawing the most current when the output swings down close to the negative rail voltage, and drawing the least current when the output swings close to the power supply rail voltage"
  Reply With Quote
Old 4th December 2006, 08:11 PM   #4
diyAudio Member
 
Wavebourn's Avatar
 
Join Date: Sep 2006
Location: Pleasant Hill, CA
Send a message via Skype™ to Wavebourn
It is what I always did: pushed crossover distortions to higher powers (A+C design), or avoided them completely using emitter, or source, or both followers, loaded by a constant current source that follows the output signal, "drawing the most current when the output swings down close to the negative rail voltage, and drawing the least current when the output swings close to the power supply rail voltage". I don't understand what is new in their design, and which "invention" are they going to protect by the patent?
It is the same cheating with fancy words, like similar British patent, about "Current Dumping that uses bridges".
__________________
The Devil is not so terrible as his math model is!
  Reply With Quote
Old 4th December 2006, 08:17 PM   #5
diyAudio Member
 
Wavebourn's Avatar
 
Join Date: Sep 2006
Location: Pleasant Hill, CA
Send a message via Skype™ to Wavebourn
Here is my example of what they are going to patent:

Click the image to open in full size.
__________________
The Devil is not so terrible as his math model is!
  Reply With Quote
Old 4th December 2006, 08:21 PM   #6
diyAudio Member
 
Wavebourn's Avatar
 
Join Date: Sep 2006
Location: Pleasant Hill, CA
Send a message via Skype™ to Wavebourn
..and here is again my example of crossover distortions shifted to less audible powers:

Click the image to open in full size.

The question is, will they try to sue me if I decide to sell my projects that include what they patented after I designed them? Are publiucations on forums enough to protect me against their lawers?
__________________
The Devil is not so terrible as his math model is!
  Reply With Quote
Old 4th December 2006, 10:15 PM   #7
diyAudio Member
 
Wavebourn's Avatar
 
Join Date: Sep 2006
Location: Pleasant Hill, CA
Send a message via Skype™ to Wavebourn
Also, removing crossover distortions from opamps, very old and good working trick... However, resistors don't provide a current that follows output signal, but anyway the current they provide shift bias so crossover distortions if ever exist are less audible than on zero power...

Click the image to open in full size.
__________________
The Devil is not so terrible as his math model is!
  Reply With Quote
Old 4th December 2006, 10:31 PM   #8
diyAudio Member
 
Wavebourn's Avatar
 
Join Date: Sep 2006
Location: Pleasant Hill, CA
Send a message via Skype™ to Wavebourn
...and, finally, complementary "Tango" pairs, when BJTs are biased in A class, results again in shifting crossover distortions to less audible powers.

Click the image to open in full size.

(the example above uses unbiased version when powerful driver works in class A: http://www.diyaudio.com/forums/showt...44#post1072644 )

__________________
The Devil is not so terrible as his math model is!
  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
Alternative Active Current Source for Aleph-X ?? EUVL Pass Labs 17 8th February 2012 04:31 AM
Aleph-type current source, but source follower this time tschrama Pass Labs 4 29th July 2005 01:55 PM
Active Current Source for TDA1543 stefanobilliani Digital Source 17 12th November 2003 03:18 PM
Source follower electret mike -> use with current source? capslock Solid State 1 28th February 2003 01:54 PM
Active current source or power resistor? woody Everything Else 2 19th September 2002 04:33 AM


New To Site? Need Help?

All times are GMT. The time now is 01:44 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