5654 (6ak5) line stage in triode mode - Page 2 - 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 30th November 2010, 07:34 AM   #11
diyAudio Member
 
Join Date: Aug 2010
Location: Italy
Thanks everybody for the comments and info, honestly I've a bunch of this tubes and I'm triyng to understand if I can use them not only for a CD Buffer stage (http://www.diyaudio.com/forums/tubes-valves/96681-tube-buffer-6j1-5654-6ak5.html).
Looking at the curves of this tubes I already realized that the main issue is the input signal, 2V is little bit high ! Unfortunately I'm not so good in theroetical issues, and may be some alternative idea may take these tubes to a different life.
To me the curves in triode mode looks good enough, what I don't see a good idea is to use it as pentode.
I know that in triode mode the gain is low, but this is what I want, at the moment I've a 300B amplifier with a 6SN7 line stage in mu-follower configuration, and to me the gain is too high.
For sure any tube may be better, but why don't try it? It wouldn't be the best line stage but, as any other tube, it could have his character!!
So let's go on with ideas, in a couple of week I would start building a first prototype.
Thanks again.
  Reply With Quote
Old 30th November 2010, 08:55 AM   #12
diyAudio Member
 
Wavebourn's Avatar
 
Join Date: Sep 2006
Location: Pleasant Hill, CA
Send a message via Skype™ to Wavebourn
It is a nice tube. It can work on very low anode voltages. When triode connected it is very similar to 6S1P tube:

http://www.cqham.ru/tubes/soviet/pdf/6s1p.pdf
__________________
"Our youth [...] have bad manners, contempt for authority; they show disrespect for their elders, contradict their parents, [...] and tyrannize their teachers. -- Plato, 447-367 BCE
  Reply With Quote
Old 30th November 2010, 05:16 PM   #13
DF96 is offline DF96  England
diyAudio Member
 
Join Date: May 2007
I have now had a look at the triode curves, as suggested by DT. Triode connection seems to improve things more than I expected, so you could use it as a line stage although there is not much margin for error and the gain would be rather high. An active load would help reduce distortion. So perhaps I was wrong, but not seriously wrong?
  Reply With Quote
Old 30th November 2010, 05:30 PM   #14
diyAudio Member
 
Wavebourn's Avatar
 
Join Date: Sep 2006
Location: Pleasant Hill, CA
Send a message via Skype™ to Wavebourn
Quote:
Originally Posted by DualTriode View Post
Hello,
The 6AK5 triode connected plate curves look like it can be biased for 2 volt input to me.
http://www.mif.pg.gda.pl/homepages/f...138/5/5654.pdf (see the last page)
Hmmm... I tried again, but it still says, "Page not found"...
__________________
"Our youth [...] have bad manners, contempt for authority; they show disrespect for their elders, contradict their parents, [...] and tyrannize their teachers. -- Plato, 447-367 BCE
  Reply With Quote
Old 30th November 2010, 06:05 PM   #15
taj is offline taj
diyAudio Member
 
taj's Avatar
 
Join Date: Feb 2005
Works for me!
  Reply With Quote
Old 30th November 2010, 06:49 PM   #16
diyAudio Member
 
Wavebourn's Avatar
 
Join Date: Sep 2006
Location: Pleasant Hill, CA
Send a message via Skype™ to Wavebourn
It works now, thanks!
__________________
"Our youth [...] have bad manners, contempt for authority; they show disrespect for their elders, contradict their parents, [...] and tyrannize their teachers. -- Plato, 447-367 BCE
  Reply With Quote
Old 1st December 2010, 08:03 AM   #17
diyAudio Member
 
Join Date: Aug 2010
Location: Italy
I really apologize for my ignorance, what do you mean for actve load? a Tranformer? If so which charateristic should it have? Do you have an example or some documentation I can look at?
  Reply With Quote
Old 1st December 2010, 02:35 PM   #18
diyAudio Member
 
Join Date: Aug 2009
Location: Sacramento
Hello francolacc,
A Mu-Follower is a example of a classic actively loaded common cathode amplifier. The top triode is the active load.
The Valve Wizard -Mu Follower
For starters keep it simple try the circuit in post number 3. You will need a capacitor at the input ~ 0.47 uf. You will like the results.
DT
All just for fun!
  Reply With Quote
Old 28th December 2010, 12:47 PM   #19
diyAudio Member
 
Join Date: Oct 2009
Quote:
Originally Posted by euro21 View Post
Try this operating point.
Hi Euro21! triode connecting 6ak5, mu = 20, everything looks very promising of your 6ak5 design.

As I have some 6ak5 , rca 1619 sitting around in my tool box, I am tempted to build a SE amp based on your design. However, it seems to be difficult to sequeeze more than 1W or so from 1619 triode mode. Do you have any recommendation of 1619 working point? or any modification of the following circuit?
Attached Images
File Type: jpg screenshot.jpg (94.5 KB, 495 views)
Attached Files
File Type: zip 6ak5_rca1619.zip (3.1 KB, 75 views)
  Reply With Quote
Old 28th December 2010, 05:11 PM   #20
diyAudio Member
 
Join Date: Aug 2010
Location: Italy
I finished a first prototype right now, and..... WORKS! It's still without a transformer since I'm waiting for it and was too impatient, but I've to say that the result is good. As soon as I've the transformer I'll test it and after I'll build the definitive 5654 line amplifier. I'm also planning to make a second stage with a cathode follower, I've to think about witch tube use... do you think that a 5654 should be a goof one? If so please help me with some example. Anyway the schema is the one at post 3.
  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 12:46 PM
6ak5/5654 plate resistance rauze Tubes / Valves 7 17th September 2008 02:28 AM
6AK5 Triode Curves dsavitsk Tubes / Valves 2 29th March 2007 06:20 PM


New To Site? Need Help?

All times are GMT. The time now is 12:34 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