6e5p WCF headphone amp with no cap! - Page 6 - diyAudio
Go Back   Home > Forums > Amplifiers > Tubes / Valves

Tubes / Valves All about our sweet vacuum tubes :) Threads about Musical Instrument Amps of all kinds should be in the Instruments & Amps forum

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 1st June 2012, 11:10 AM   #51
diyAudio Member
 
Join Date: May 2007
This topology should do it with only one the lovely 6E5Ps at 100V/60mA. No caps and a low Zout with the help of a "garypimmish" battery-biased CCS(cascode is no problem). Will keep THD well below 0,1% too.
Attached Images
File Type: png moo.png (61.8 KB, 155 views)
  Reply With Quote
Old 1st June 2012, 11:15 AM   #52
mogliaa is offline mogliaa  United Kingdom
diyAudio Member
 
mogliaa's Avatar
 
Join Date: Dec 2009
Location: London
Interesting Lars. Can you please explain the topology, is it an anti-triode configuration?
thanks
Ale
__________________
"A mistake is always forgivable, rarely excusable and always unacceptable. " (Robert Fripp)
http://www.bartola.co.uk/valves/
  Reply With Quote
Old 1st June 2012, 11:27 AM   #53
diyAudio Member
 
Join Date: May 2007
Havenīt cared to name or define it. But anything with "mu" will do.

With P-channel depletion MOSFETs on the market it would have been even easier to accomplish.
  Reply With Quote
Old 1st June 2012, 11:30 AM   #54
mogliaa is offline mogliaa  United Kingdom
diyAudio Member
 
mogliaa's Avatar
 
Join Date: Dec 2009
Location: London
Quote:
Originally Posted by revintage View Post
Havenīt cared to name or define it. But anything with "mu" will do.

With P-channel depletion MOSFETs on the market it would have been even easier to accomplish.
Well, it looks to me like a gyrator with a mu or anti-triode output (I think Michael Koster named it or referenced it as such), correct?
__________________
"A mistake is always forgivable, rarely excusable and always unacceptable. " (Robert Fripp)
http://www.bartola.co.uk/valves/
  Reply With Quote
Old 1st June 2012, 11:38 AM   #55
diyAudio Member
 
Join Date: May 2007
Same function. Gyrator this time?
Attached Images
File Type: png moob.png (61.1 KB, 149 views)

Last edited by revintage; 1st June 2012 at 11:41 AM.
  Reply With Quote
Old 1st June 2012, 11:48 AM   #56
mogliaa is offline mogliaa  United Kingdom
diyAudio Member
 
mogliaa's Avatar
 
Join Date: Dec 2009
Location: London
Quote:
Originally Posted by revintage View Post
Same function. Gyrator this time?
Indeed, but I thought that when the output was taken from a midpoint of the source resistor, that would provide the lowest Zout (Zout/2) compared to the gyrator equivalent?
Wouldn't that be the case when taking the output from the pot?
__________________
"A mistake is always forgivable, rarely excusable and always unacceptable. " (Robert Fripp)
http://www.bartola.co.uk/valves/
  Reply With Quote
Old 1st June 2012, 11:59 AM   #57
diyAudio Member
 
Join Date: May 2007
NO, no gyrator at all this time this time. Look at the battery as a signal short. If you take the output from the midpoint, Zout gets higher, not lower. When taken directly from the source Zout will be just a few ohms. When taken from the midpoint you will get a useless ballpark Zout of 30-40ohm. So Antitriode is no option here.
  Reply With Quote
Old 1st June 2012, 12:14 PM   #58
mogliaa is offline mogliaa  United Kingdom
diyAudio Member
 
mogliaa's Avatar
 
Join Date: Dec 2009
Location: London
Ops, my fault. I didn't look at the circuit properly. So it's just a gyrator...
Will simulate this one then to study it a bit more, thanks!
__________________
"A mistake is always forgivable, rarely excusable and always unacceptable. " (Robert Fripp)
http://www.bartola.co.uk/valves/
  Reply With Quote
Old 1st June 2012, 12:24 PM   #59
diyAudio Member
 
Join Date: May 2007
Noooo, the second one is NO gyrator, the cap can be omitted.

Question is wether the the battery would harm fidelity? No current through it so one could try Lithium cells. Thorsten L. used them in series with signal when adding grid bias. Think he bypassed with a small cap and a large resistor though.

Looking forward to your findings. Have never used and will never use headphones but I still find this subject amusing.

Last edited by revintage; 1st June 2012 at 12:29 PM.
  Reply With Quote
Old 1st June 2012, 02:05 PM   #60
TheGimp is offline TheGimp  United States
diyAudio Member
 
TheGimp's Avatar
 
Join Date: Aug 2009
Location: Johnson City, TN
Headphones make my hearing aids whistle.

Interesting design.
  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
Low power JFET WCF Osvaldo de Banfield Solid State 2 20th April 2012 12:10 PM
What would be the correct output cap for this OTL Headphone Amp? pingfloid Tubes / Valves 26 2nd January 2012 03:51 PM
6E5P Jaime Tubes / Valves 6 10th March 2011 07:17 PM
Humming from WCF but not SRPP Brit01 Tubes / Valves 5 22nd August 2010 08:37 PM
6e5p Vladi59 Swap Meet 0 18th March 2009 07:26 PM


New To Site? Need Help?

All times are GMT. The time now is 03:49 PM.


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