Substitute 6AQ8 for my 6CG7's - 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 18th June 2013, 10:12 PM   #1
Einric is offline Einric  United States
diyAudio Member
 
Einric's Avatar
 
Join Date: Feb 2011
Location: Bozeman, MT
Default Substitute 6AQ8 for my 6CG7's

I need about 6-9db more gain in my Aikido.
Would a 6AQ8 be a suitable front end substitute?
There is a matched & balanced quad of NOS Tungsram 6AQ8's on E-Bay for $40.
Then I would have a backup set of each.

I'd run the 6AQ8's in front with the 6CG7 follower.
  Reply With Quote
Old 19th June 2013, 08:10 AM   #2
DF96 is offline DF96  England
diyAudio Member
 
Join Date: May 2007
6AQ8/ECC85 would give you 10-12dB more gain. You might need to adjust the cathode resistors to get the bias right.

Unusual request - most people find the Aikido has too much gain!
  Reply With Quote
Old 19th June 2013, 09:56 AM   #3
AJT is offline AJT  Philippines
diyAudio Moderator
 
AJT's Avatar
 
Join Date: May 2003
Location: Palatiw, Pasig City
i switch to 6r-rh2 when i wanted more gain, most of the time i go with 6r-rh8/6CG7/6H32
__________________
the best advertisement for a good audio design is the number of diy'ers wanting to build it after all the years....never the say so of so called gurus....
  Reply With Quote
Old 19th June 2013, 12:25 PM   #4
Einric is offline Einric  United States
diyAudio Member
 
Einric's Avatar
 
Join Date: Feb 2011
Location: Bozeman, MT
I am driving a Pass F4 (-.3db gain) on some pretty low efficiency speakers.
I'm really only looking for about 6db more I think.
I don't want to sacrifice the superb sound I have with my 6CG7's though.
I am running 290V B+ for what that's worth.
Switching to 12V heaters is simple with my Aikido since I'm running my 6.3v heaters in series right now.

Last edited by Einric; 19th June 2013 at 12:28 PM.
  Reply With Quote
Old 19th June 2013, 12:45 PM   #5
diyAudio Member
 
Join Date: Nov 2009
Location: Cortez, CO
6N1P is supposed to sound like a 6CG7, but with more gain (35). Or you can try a 6BQ7, 6DJ8, or 6N23P.

Look on the 9 pin Aikido pdf and it will list a number of tubes and their gains.

http://www.tubecad.com/2006/09/18/Ai...%20A%20PCB.pdf

Last edited by DeathRex; 19th June 2013 at 12:53 PM.
  Reply With Quote
Old 19th June 2013, 10:36 PM   #6
Einric is offline Einric  United States
diyAudio Member
 
Einric's Avatar
 
Join Date: Feb 2011
Location: Bozeman, MT
Yes, I have my manual and I can see the gain levels.
I know what some of my options are but I'm suggestions from personal experience here.
  Reply With Quote
Old 19th June 2013, 10:42 PM   #7
AJT is offline AJT  Philippines
diyAudio Moderator
 
AJT's Avatar
 
Join Date: May 2003
Location: Palatiw, Pasig City
i operated mine at B+ of 300volts...
Attached Images
File Type: jpg IMG_3298.JPG (652.4 KB, 87 views)
File Type: jpg IMG_2593.jpg (591.6 KB, 87 views)
__________________
the best advertisement for a good audio design is the number of diy'ers wanting to build it after all the years....never the say so of so called gurus....
  Reply With Quote
Old 19th June 2013, 11:14 PM   #8
diyAudio Member
 
Join Date: May 2003
Location: Prescott AZ
I have run a number of tubes up front. The one I settled on is 6n1p. A bit more gain than 6CG7 and they simply sound better to me. I have also used 6n23p successfully.
__________________
MG
  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
FS: Telefunken ECC85 6AQ8 radiostar Swap Meet 1 9th September 2011 12:36 PM
Lafayette LT-100 and 6AQ8 tubes rickl Tubes / Valves 5 17th April 2008 07:54 PM
6gu7 a sub for 6cg7/6fq7? jarthel Tubes / Valves 5 17th May 2007 07:35 AM
Ppp 6cg7/6sn7 Colt45 Tubes / Valves 4 27th September 2006 10:10 PM
Best bias for 6cg7 rossdt Tubes / Valves 5 22nd July 2006 08:51 PM


New To Site? Need Help?

All times are GMT. The time now is 09:47 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