question about twin triode 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 19th February 2009, 03:25 AM   #1
diyAudio Member
Join Date: Aug 2006
Default question about twin triode tubes

There are two sets of operating stats for this tube. Is one set of stats for the first triode and the second set of stats for the 2nd triode, or are the two internal triodes the same ? Are these stats just representative of what could be expected with different plate voltages ?

Basically , do the two triodes have the same specs, or are they as different as the two sets of specs indicate ?

Keep it simple
My Page Of SV1000 and DIY Stereo Links
  Reply With Quote
Old 19th February 2009, 03:52 AM   #2
Sheldon is offline Sheldon  United States
diyAudio Member
Join Date: Dec 2003
Location: San Diego
The two different operating stats, are for two different operating points. They apply to each triode. The confusion is caused by the heading for the interelectrode capacitances shown above the operating parameters. Those are slightly different for each triode, because the tube is not a perfect mirror image section to section. The distance from component to pin varies a little. But, the triode 1, triode 2 heading only applies to the capacitances. Clear as mud?

Now to confuse you a bit more; sometimes tubes contain dissimilar triodes. Of course, those will have completely different operating parameters and are shown as such.

And some tubes, such as the 6922 have identical triodes, as far as an amplifier, but are designed to be used in a cascode. In this case, the tolerance for cathode to heater voltage can be different, as one section should be used for the top and one for the bottom of the cascode. If used a just a twin triode, they are treated the same.

  Reply With Quote
Old 19th February 2009, 04:39 AM   #3
diyAudio Member
Join Date: Aug 2006
Thanks. You hit the nail on the head. I wasn't sure if the heading showing the capacitance for the 2 sections dropped down to the rest of the stats. Now I see .

I was wondering why everyone thought 12AX7's were so great when they seemed to be such a mismatched set of triodes.

That clears it up. Thanks again...........................Blake
Keep it simple
My Page Of SV1000 and DIY Stereo Links
  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
Stereo Buffer with a single twin triode Brit01 Tubes / Valves 43 29th July 2009 02:32 PM
Best/favorite CF NOS noval twin triode? leadbelly Tubes / Valves 34 19th April 2008 04:37 PM
Any subs for 6N1 & 6N2 twin triode valves? rcavictim Tubes / Valves 39 20th April 2005 02:19 PM
mmm.... zero-bias class B twin triode amp Circlotron Tubes / Valves 6 5th March 2003 12:49 AM

New To Site? Need Help?

All times are GMT. The time now is 01:57 PM.

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