6V6 line preamp - Page 17 - 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 December 2009, 08:57 AM   #161
tubo is offline tubo  Philippines
diyAudio Member
 
Join Date: Apr 2007
Location: Mundelein, Illinois
hi salas,

the 6v6 anode follower has way too much gain. how is the sound quality of the 6v6 buffer cathode follower?im thinking of breadbording the circuit it is just a few resistors away.
  Reply With Quote
Old 30th December 2009, 09:01 AM   #162
Salas is offline Salas  Greece
diyAudio Chief Moderator
 
Salas's Avatar
 
Join Date: Oct 2002
Location: Athens-Greece
15dB it has as a preamp with gain. If you reconfigure it as a buffer, it has splendid quality again as far as cathode followers go. Worths to check it out. FT-2 or FT-3 for input.
  Reply With Quote
Old 30th December 2009, 10:04 AM   #163
diyAudio Member
 
Join Date: Apr 2003
Location: West Yorkshire, UK.
The gain of a real "anode follower" can be adjusted from maximum gain to unity gain by the ratio of two resistors in the circuit. Please don't use the term "anode follower" to designate a normal grounded cathode amplifier stage : it muddles things up and reduces the number of useable designations just as Bruce Rozenblit has with his misuse of "grounded grid".
  Reply With Quote
Old 30th December 2009, 10:21 AM   #164
Salas is offline Salas  Greece
diyAudio Chief Moderator
 
Salas's Avatar
 
Join Date: Oct 2002
Location: Athens-Greece
Grounded cathode it normally is. OK Tubo?
  Reply With Quote
Old 30th December 2009, 12:53 PM   #165
tubo is offline tubo  Philippines
diyAudio Member
 
Join Date: Apr 2007
Location: Mundelein, Illinois
thanks for clarifying guys. how do i reduce the gain of the circuit?
  Reply With Quote
Old 30th December 2009, 07:59 PM   #166
Salas is offline Salas  Greece
diyAudio Chief Moderator
 
Salas's Avatar
 
Join Date: Oct 2002
Location: Athens-Greece
Not inherently drastically so, you can't. Tweaking current will be still about there for gain, only funnier working points. If you want an input Lpad, I don't advise it on transparency grounds, ups source impedance and interaction with Mr. Miller. Go buffer and listen first.
  Reply With Quote
Old 31st December 2009, 02:54 AM   #167
tubo is offline tubo  Philippines
diyAudio Member
 
Join Date: Apr 2007
Location: Mundelein, Illinois
ill try the buffer and will report back. thanks
  Reply With Quote
Old 31st December 2009, 09:11 PM   #168
tubo is offline tubo  Philippines
diyAudio Member
 
Join Date: Apr 2007
Location: Mundelein, Illinois
hi salas,

i tried 10k anode resistor and it sounded much better.all of the frequency spectrum opened up especially the bass. the harshness was gone and most of all i now have a usable range on my volume pot. what happened when i made the change?i know that increasing the load lowers THD. do i need to change the cathode resistor value if so what?


happy new year to all,

ivan
  Reply With Quote
Old 31st December 2009, 10:09 PM   #169
diyAudio Member
 
Joshua_G's Avatar
 
Join Date: Nov 2008
Location: Small village, Israel
Salas, in the schematic you showed earlier in the thread, you use tubes like 5R4GY, 5U4G or GZ34 for the rectifier. Wouldn't rubes like 6X4 or EZ81 do?
  Reply With Quote
Old 1st January 2010, 02:53 PM   #170
Salas is offline Salas  Greece
diyAudio Chief Moderator
 
Salas's Avatar
 
Join Date: Oct 2002
Location: Athens-Greece
Anything that can give 100mA at 400V without stress will do. So about 340V will be feasible counting the Vdif needs of regs. 45mA is for two channels, but 100mA is good for headroom or in case of shunt reg extra constant current needs.
  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 me design my DAC/Line Preamp. kuroguy Tubes / Valves 7 2nd April 2009 08:31 PM
preamp line ctt richwalters Tubes / Valves 1 7th March 2008 04:34 PM
Preamp for Line In and Mic blur Instruments and Amps 1 4th January 2007 04:02 PM
Line stage preamp, based on SY's "Heretical Unity gain line stage" Danko Tubes / Valves 23 18th July 2005 04:07 AM
Line preamp for 2A3 amp Petman Tubes / Valves 0 24th May 2002 03:11 PM


New To Site? Need Help?

All times are GMT. The time now is 03:38 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