First foray into tubes!! - diyAudio
Go Back   Home > Forums > Amplifiers > Tubes / Valves
Home Forums Rules Articles diyAudio Store Gallery Wiki Blogs Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

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
Thread Tools Search this Thread
Old 2nd October 2007, 10:01 PM   #1
diyAudio Member
Join Date: Jul 2005
Default First foray into tubes!!

So I figured I'd start simple.

Excuse the sideways-ness of the schematic .
I'll be building the two sides, so good for about 10w, ample through 91dB speakers.

Just curious - exactly how interchangeable would a 12AU7 be with the AX - I've known them to be swapped over in guitar amps with no problem and producing favourable results...

Should be commencing at the end of the year (college project), and some interesting addons, like a remote controlled motorised volume pot etc.


Click the image to open in full size.
  Reply With Quote
Old 2nd October 2007, 10:38 PM   #2
diyAudio Member
Join Date: Jul 2005
I must apologise for the immense picture - I had no idea this forum didn't autothumbnail . And there appears to be no ability to edit, so please accept my red faced apologies
  Reply With Quote
Old 2nd October 2007, 10:39 PM   #3
diyAudio Moderator
planet10's Avatar
Join Date: Oct 2001
Location: Victoria, BC, NA, Sol III
Blog Entries: 5
Actually the image has been replaced by a generic "imaged hosted by AngelFire" graphic.

If you can't shrink the image to fit (1000x1000 and <100kB) mail me and i can help out.

community sites,, ........ commercial site planet10-HiFi
p10-hifi forum here at diyA
  Reply With Quote
Old 3rd October 2007, 12:05 AM   #4
SY is offline SY  United States
diyAudio Moderator
SY's Avatar
Join Date: Oct 2002
Location: Chicagoland
Blog Entries: 2
In a hifi amp where gain and distortion are more important than in MI amps, a 12AU7 and 12AX7 should not be interchanged. Despite the same pinout and heater ratings, they're vastly different tubes.

Welcome to the world of thermionics!
"You tell me whar a man gits his corn pone, en I'll tell you what his 'pinions is."
  Reply With Quote
Old 3rd October 2007, 07:21 AM   #5
diyAudio Member
Join Date: Jul 2005
Point taken, the AX7 stays! Can one edit posts here?!

  Reply With Quote
Old 3rd October 2007, 07:51 AM   #6
diyAudio Moderator Emeritus
ray_moth's Avatar
Join Date: Jan 2004
Location: Jakarta
Editing posts works OK, providing you don'r leave it too long before you do so. A useful tool is the preview button, which helps you get it right before posting.

A bit more about the 12AU7: this is not a very linear tube and there are better 9-pin alternatives, like the 6CG7 and 6FQ7. They're not quite so easy to find and may cost a bit more, but they are quite linear - true miniaturizations of the 6SN7. They're not able to sub successfully for a 12AX7, though, anymore than the 12AU7 is, and their pin-outs are different anyway.
  Reply With Quote
Old 3rd October 2007, 07:59 AM   #7
diyAudio Member
Join Date: Jul 2005
12AX7 stays so...It's more of an experiment than anything

  Reply With Quote
Old 3rd October 2007, 01:22 PM   #8
diyAudio Member
Sal Brisindi's Avatar
Join Date: Nov 2006
Here is a resized jpg of the 6v6 amp above. I also turned it 90 degrees.

Sal Brisindi
Click the image to open in full size.
  Reply With Quote
Old 3rd October 2007, 01:51 PM   #9
diyAudio Member
Join Date: Jul 2005 why couldn't I edit my post and do that? I'd resized it and all !!


I see now that I can edit my posts, now that I've come out from being under moderation?! Cheers!
  Reply With Quote
Old 3rd October 2007, 02:06 PM   #10
diyAudio Member
Join Date: May 2004
Location: WI
You can edit your posts if you're logged in; you'll see the button on your post just below and to the right of your text once it's been submitted.

Perhaps you logged out and then went back in to read your post without logging on?
  Reply With Quote


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 Noob! need help with tubes lots of tubes therapy_fan Tubes / Valves 15 29th January 2009 09:01 PM
WTT: Various tubes for 6CA4/EZ81 rectifier tubes GordonW Swap Meet 4 27th August 2008 12:37 AM
CV428 tubes (Loktal 807) tubes FS mobyd Swap Meet 3 2nd January 2008 11:26 AM
First Power Amp Foray Wyloch Solid State 2 8th December 2005 06:35 AM
many new tubes and tubes meter for sale elviukai Swap Meet 4 30th October 2003 09:22 AM

New To Site? Need Help?

All times are GMT. The time now is 06:40 AM.

vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
Copyright 1999-2017 diyAudio

Content Relevant URLs by vBSEO 3.3.2