cathode follower tube buffer using 6n6p - 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 24th June 2010, 02:23 PM   #1
diyAudio Member
 
Join Date: Feb 2009
Default cathode follower tube buffer using 6n6p

I have little experience with tube amps (built 1 spud) and have 8 Russian 6n6p tubes. Im building a preamp and would like to use the tubes as a buffer for the output to lower the impedance after the pot.

Is there a simple schematic someone has for this using a cathode buffer with 1 tube? Im in the USA so I was thinking of just getting 2 6.3vac transformers and running 1 to the wall to step down to 6.3, then connect the other one to step it back to 120vac and use a full bridge rec to convert to 170vdc.

Can i just copy Lamps version that he uses for his dac's?
  Reply With Quote
Old 24th June 2010, 09:56 PM   #2
Arnulf is offline Arnulf  Europe
diyAudio Member
 
Join Date: Feb 2009
Read: The Valve Wizard -Cathode Follower

And yes, your transformer arrangement is sound.
__________________
mod verb, transitive /mod/ to state that one is utterly clueless about the operation of device to be "modded" and into "fixing" things that are not broken; "My new amplifier sounds great so I want to mod it."
  Reply With Quote
Old 25th June 2010, 01:12 AM   #3
Gordy is offline Gordy  United Kingdom
diyAudio Member
 
Join Date: Nov 2006
Quote:
Originally Posted by nightanole View Post
Is there a simple schematic someone has for this using a cathode buffer with 1 tube?
Consider the DC coupled follower designed and documented by forum member SY. It's called Heretic: A Heretical Unity gain line stage

Quote:
Originally Posted by nightanole View Post
Can i just copy Lamps version that he uses for his dac's?
You mean this? Preamplifier_with_HEAD

You can adapt it, but the performance may be mediocre.
  Reply With Quote
Old 25th June 2010, 02:13 AM   #4
diyAudio Member
 
Join Date: Apr 2004
Location: Monroe Township, NJ
While undoubtedly sound, SY's design is anything but simple and could be a trap for a builder with little experience.

FWIW, I suggest 10M45S constant current sink loaded cathode followers and a bipolar PSU. That sort of arrangement places only 1 cap., at the unit's O/P, in the signal path. A 4.7 μF metalized polypropylene part bypassed by a 470 nF. 716P series Orange Drop does that job well, without spending a lot.

A $25 AnTek model AN-05T160 power trafo looks like a reasonable fit for the job. To get a bipolar supply, each rail would be 1/2 wave rectified, but making the 1st filter caps. big deals with that matter. A single filter choke can be shared between the 2 rails, in the grounded leg. A pair of 600 PIV Schottky diodes for rectification are inexpensive enough and yield "noiseless" operation.
__________________
Eli D.
  Reply With Quote
Old 25th June 2010, 03:12 AM   #5
diyAudio Member
 
Join Date: Feb 2009
Oh man Eli is following me again. Um with a BP supply i halve my voltage so supply caps would be alot cheaper. Any schematics or something to go on? Since im a beginer i cant make anything from scratch. I just wanted to get some tube sound to my Tamp and 3886 amp i built up.


Heres what i was going to adapt.

http://www.lampizator.eu/lampizator/...X/IMG_5144.jpg

its got 2 caps in the audio path, but the first can be small so i can get something nice. The output cap might set me back alittle if i go full metal film.
  Reply With Quote
Old 25th June 2010, 09:40 PM   #6
smbrown is offline smbrown  United States
diyAudio Member
 
smbrown's Avatar
 
Join Date: Jun 2004
Location: Portland, OR
Nightanole, But that's not a cathode follower, it's an anode follower. However, with the lowish plate impedance of the 6n6, you may not need a cathode follower. I use a 6n6 preamp and take the output from the plate, no problem.
  Reply With Quote
Old 25th June 2010, 09:43 PM   #7
SY is offline SY  United States
diyAudio Moderator
 
SY's Avatar
 
Join Date: Oct 2002
Location: Chicagoland
Blog Entries: 1
It's not even an anode follower, it's a common cathode amplifier. The design is... questionable.
__________________
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 25th June 2010, 10:19 PM   #8
diyAudio Member
 
Ezequiel (kel)'s Avatar
 
Join Date: Oct 2009
Location: Brasil
see this, but it has to change for 6n6p, that and a very good blog 10000 circuits...

http://circuitoseletronics.blogspot....-follower.html

Moderator Warning Note: the link does take you to a cathode follower, but also opens new windows for at string of advertisements
__________________
sorry if wrong, my English is google translator
  Reply With Quote
Old 26th June 2010, 01:50 AM   #9
diyAudio Member
 
Join Date: Feb 2009
Sorry wrong lamp

http://www.lampizator.eu/LAMPIZATOR/...X/IMG_5143.jpg

heres the cathode version
  Reply With Quote
Old 26th June 2010, 02:01 AM   #10
diyAudio Member
 
Wavebourn's Avatar
 
Join Date: Sep 2006
Location: Pleasant Hill, CA
Send a message via Skype™ to Wavebourn
Quote:
Originally Posted by nightanole View Post
Sorry wrong lamp

http://www.lampizator.eu/LAMPIZATOR/...X/IMG_5143.jpg

heres the cathode version
Nope. It's still a common cathode inverting amp.

Try again!
__________________
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
help !! 5687 cathode follower as cd buffer costa23 Digital Source 0 25th March 2010 02:06 AM
6N6P cascode + 6AS7 Cathode follower croccodillo Tubes / Valves 12 15th September 2007 10:33 AM
Cathode Follower Buffer Input Impedance xcortes Tubes / Valves 5 1st December 2005 06:10 PM
Basic Cathode Follower buffer dsavitsk Tubes / Valves 11 26th June 2005 05:25 PM
Question about direct coupling a anode follower into a cathode follower. G Tubes / Valves 45 29th July 2004 07:47 PM


New To Site? Need Help?

All times are GMT. The time now is 10:29 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