5654 (6ak5) line stage in triode mode - Page 3 - 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 29th December 2010, 08:57 PM   #21
euro21 is offline euro21  Hungary
diyAudio Member
 
Join Date: Sep 2004
Location: Budapest
Quote:
Originally Posted by sulcorebutia View Post
more than 1W or so from 1619 triode mode.
Triode mode: 5K:8 transformer, 330 ohm cathode res., 300V/41mA operating point.

0.8W, 1.7% THD.
Finito .

Try pentode mode, with 10K:8 OPT.
4.7W/10% THD.
Attached Images
File Type: jpg 1619_pentode.jpg (302.2 KB, 518 views)
Attached Files
File Type: zip 6ak5_1619_pentode.zip (5.2 KB, 57 views)
  Reply With Quote
Old 29th December 2010, 10:38 PM   #22
diyAudio Member
 
Join Date: Oct 2009
Quote:
Originally Posted by euro21 View Post
Triode mode: 5K:8 transformer, 330 ohm cathode res., 300V/41mA operating point.

0.8W, 1.7% THD.
Finito .

Try pentode mode, with 10K:8 OPT.
4.7W/10% THD.
Thanks a lot! I will give it a try
  Reply With Quote
Old 29th December 2010, 10:44 PM   #23
diyAudio Member
 
Join Date: Oct 2009
Quote:
Originally Posted by euro21 View Post
Triode mode: 5K:8 transformer, 330 ohm cathode res., 300V/41mA operating point.

0.8W, 1.7% THD.
Finito .

Try pentode mode, with 10K:8 OPT.
4.7W/10% THD.
Euro21, in addition of triode mode and pentode mode. Will there be any advantage in both power/distortion by running this directly heated pentode in Ultralinear mode over pure pentode mode?

Last edited by sulcorebutia; 29th December 2010 at 10:57 PM.
  Reply With Quote
Old 30th December 2010, 09:52 AM   #24
diyAudio Member
 
Join Date: Aug 2010
Location: Italy
i got the iron and i tested the almost definitive circuit with good result i'll post some picture as soon as possible, but i wold like to add a cathode follower stage dc couplude and I would lke to use 6au6 tube, any schema to help me?
  Reply With Quote
Old 30th December 2010, 11:58 AM   #25
SY is offline SY  United States
diyAudio Moderator
 
SY's Avatar
 
Join Date: Oct 2002
Location: Chicagoland
Blog Entries: 1
Why a 6AU6? That's not a particularly good tube for a cathode follower.
__________________
And while they may not be as strong as apes, don't lock eyes with 'em, don't do it. Puts 'em on edge. They might go into berzerker mode; come at you like a whirling dervish, all fists and elbows.
  Reply With Quote
Old 30th December 2010, 07:22 PM   #26
diyAudio Member
 
Join Date: Aug 2010
Location: Italy
Simply because I've some of these tubes, but I've also some EF184 and a lot of EF93, do you think that I can use some of them? If so has, some of you, any useful schema for a DC coupled cathode follower ?
  Reply With Quote
Old 6th January 2011, 10:37 PM   #27
diyAudio Member
 
Join Date: Aug 2010
Location: Italy
I've found some 6688 / E180F pentode and I was wondering if they could be good candidates for a dc coupled cathode follower stage. Is there anybody that can help me in completing this project ?
Thanks
  Reply With Quote
Old 6th January 2011, 11:16 PM   #28
SY is offline SY  United States
diyAudio Moderator
 
SY's Avatar
 
Join Date: Oct 2002
Location: Chicagoland
Blog Entries: 1
Just curious, why do you want to use a pentode for this? No real performance advantage over triode and higher parts count.

Whichever direction you go, the figure of merit is the transconductance. Output impedance is roughly the reciprocal of transconductance, so high gm = low source Z. That's why some of us have bitten the bullet and gone to MOSFET source followers to drive output stages.
__________________
And while they may not be as strong as apes, don't lock eyes with 'em, don't do it. Puts 'em on edge. They might go into berzerker mode; come at you like a whirling dervish, all fists and elbows.
  Reply With Quote
Old 17th January 2014, 02:01 AM   #29
diyAudio Member
 
Join Date: Oct 2012
Hi Franco,

Could you please tell me which schematic is the best for 6ak5 line stage ?? Thank you very much in advance.
  Reply With Quote
Old 3rd March 2014, 07:50 PM   #30
diyAudio Member
 
Join Date: Aug 2010
Location: Italy
The one at post #2 worked good for me followed by a 6n6p cathode follower stage. Anyway I gave it away to a friend of mine, even if it was a good sounding preamp.
  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
Tube Buffer 6J1 / 5654 (6AK5) Cobra2 Tubes / Valves 99 2nd June 2013 01:46 PM
6ak5/5654 plate resistance rauze Tubes / Valves 7 17th September 2008 03:28 AM
6AK5 Triode Curves dsavitsk Tubes / Valves 2 29th March 2007 07:20 PM


New To Site? Need Help?

All times are GMT. The time now is 07:01 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