Tube filaments in series? - 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 6th April 2007, 06:41 PM   #1
Klimon is offline Klimon  Belgium
diyAudio Member
 
Join Date: Apr 2005
Location: Leuven
Default Tube filaments in series?

Dear tube-lover,

Is it detrimental for tubes of same type and make to wire their heaters in series (e.g. to suit two 6.3V tubes with a 12.5 supply)? I know some tubes have a certain affix indicating their suitability for heaters connected in series, what about your average tube?

Cheers --- Simon
  Reply With Quote
Old 6th April 2007, 06:47 PM   #2
diyAudio Member
 
Alain Dupont's Avatar
 
Join Date: Sep 2003
Location: Paris - France
Klimon,

Go for it, without any problems, but make sure you replace the tubes in pairs...

Regards,

Alain.
__________________
Did live about 10 years in Canada
Back to France since the 1st February 2007.
  Reply With Quote
Old 6th April 2007, 06:56 PM   #3
diyAudio Member
 
Join Date: Feb 2007
Location: Near Buffalo NY USA
Scott integrateds wired 4 12ax7s in series and powered them with DC. Only the very early Scotts used AC on their heaters. Also the Dyna PAS preamps use a higher voltage DC and series the heaters... It works fine.....
__________________
The stuff you don't know always humbles us.........
  Reply With Quote
Old 6th April 2007, 06:58 PM   #4
diyAudio Member
 
Join Date: Apr 2004
Location: Monroe Township, NJ
I agree with Alain. You should be fine using a pair of tubes from the same production run.

Controlled heater warm up time is important in lengthy strings of dissimilar types rated for the same heater current. None of the heaters get overvoltaged.
__________________
Eli D.
  Reply With Quote
Old 6th April 2007, 09:19 PM   #5
diyAudio Member
 
Join Date: May 2005
Location: Pretoria, South Africa
Supporting this - best way to get dc on heaters with proper filtering (low current, high voltage). One must just watch the maximum heater-cathode voltage rating if several are used in series.
  Reply With Quote
Old 7th April 2007, 03:22 AM   #6
mach1 is offline mach1  Australia
diyAudio Member
 
mach1's Avatar
 
Join Date: Sep 2004
Location: Brisvegas
Some of the odd-voltage variants of common tubes have controlled heater warm up characterisitcs (usually around 11 secs) specially made for series wiring.

You can sometimes get 3V filament versions for a song and series heat them from a regular 6.3V tap.

pm
__________________
Au rutti wop-bop-a-loom-bop-a-boom-bam-boom - Richard Penniman
  Reply With Quote
Old 7th April 2007, 07:12 AM   #7
diyAudio Member
 
Join Date: Sep 2004
Location: UK
Some of us are old enough to remember directly heated TV sets.

All the tube heaters strung together in series across the mains.

No mains transformer and live chassis

Great fun!
  Reply With Quote
Old 7th April 2007, 09:16 AM   #8
Klimon is offline Klimon  Belgium
diyAudio Member
 
Join Date: Apr 2005
Location: Leuven
That's a clear answer, and luckily the one that opens possibilities!

Thanx,
Simon
  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
AC or DC current for 300B and 2A3 tube filaments ? Kriskom Tubes / Valves 29 22nd July 2012 03:28 PM
Switching power supply for tube filaments possible??? noyan Tubes / Valves 12 17th September 2008 01:32 AM
Series connection of filaments leadbelly Tubes / Valves 24 15th August 2007 12:12 PM
Tube filaments (heaters) power supply matejS Tubes / Valves 5 12th July 2007 05:50 PM
Low vs High aka Series vs Parallel Filaments ak_47_boy Tubes / Valves 10 22nd April 2007 06:05 PM


New To Site? Need Help?

All times are GMT. The time now is 02:00 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