filament transformer vs plate transformer - 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 12th January 2005, 03:46 AM   #1
diyAudio Member
 
Join Date: Aug 2003
Location: Indiana USA
Question filament transformer vs plate transformer

Hi all,
Does anybody know the funadamental difference between filament and plate transformer? Does filament transformer got more regulation than plate transformer, given the same output voltage?
Any expert?

LungHui Chen
  Reply With Quote
Old 12th January 2005, 04:00 AM   #2
SY is offline SY  United States
diyAudio Moderator
 
SY's Avatar
 
Join Date: Oct 2002
Location: Chicagoland
Blog Entries: 1
A filament transformer will be wound to give a voltage appropriate for filaments (or heaters), most commonly 2.5, 6.3, or 12.6V. A plate transformer will generally be wound to give an appropriate voltage for tube plates, typically in the hundreds of volts.
__________________
And while they may not be as strong as apes, don't lock eyes with 'em, don't do it. Puts 'em on edge. They might go into berzerker mode; come at you like a whirling dervish, all fists and elbows.
  Reply With Quote
Old 12th January 2005, 08:07 PM   #3
diyAudio Member
 
Join Date: Aug 2003
Location: Indiana USA
Ok,
I have some filament transformers with 80v ac... That's quiet high, isn't it? After doubling the voltage, what's the difference between a regular plate transformer?
Lchhen
  Reply With Quote
Old 12th January 2005, 08:12 PM   #4
SY is offline SY  United States
diyAudio Moderator
 
SY's Avatar
 
Join Date: Oct 2002
Location: Chicagoland
Blog Entries: 1
At 80vac, they're unlikely to be filament transformers. But with a voltage doubler, there's no reason you couldn't use tham for plate supplies.

There have been tubes made with high-ish filament voltage requirements, but they're nearly all intended for transformerless use (once common in TVs and radios, but abandoned as FAR too dangerous).
__________________
And while they may not be as strong as apes, don't lock eyes with 'em, don't do it. Puts 'em on edge. They might go into berzerker mode; come at you like a whirling dervish, all fists and elbows.
  Reply With Quote
Old 13th January 2005, 08:27 AM   #5
diyAudio Moderator Emeritus
 
ray_moth's Avatar
 
Join Date: Jan 2004
Location: Jakarta
SY already said it. The other important difference is that filament transformer secondary windings have thick wire to supply several amps, wheareas plate transformers are wound with quite thin wire because they need to supply only a fraction of an amp (typically 50 mA - 500 mA).
  Reply With Quote
Old 13th January 2005, 06:10 PM   #6
diyAudio Member
 
Shoog's Avatar
 
Join Date: Aug 2002
Location: Eire
Will the filament transformer have a poor frequency response.
I am using a filament transformer of 6.3V ac to drive some speaker line transformers in order to get 70V ac. Is the filament transformer likely to be constricting the frequency response of the line transformers ?

Shoog
  Reply With Quote
Old 14th January 2005, 03:43 AM   #7
diyAudio Member
 
Join Date: Aug 2003
Location: Indiana USA
Hi,
I know filament transformer got bigger wire and supplies a few amps...
Shoog's question is really meaningful.
Anybody else?
  Reply With Quote
Old 14th January 2005, 06:54 AM   #8
diyAudio Member
 
audiousername's Avatar
 
Join Date: Jul 2004
Location: Melbourne, Victoria
Shoog, the transformer should not have an effect on the frequency response. It is there to provide a voltage. In any case, the transformer is effectively shorted out by the last cap in the power supply (for audio signals).

The drawback of connecting two transformers in series (i.e. stepping the voltage down, then up again) is increased losses - since you are using two transformers. As such it is possible (though not very likely) that the power supply will have such poor regulation that it will sag on demanding passages of music (especially containing bass), but this is the effect of reduced power, not compromised frequency response.

In any case, I don't quite get what you mean by 'constricting the frequency response of line transfomers' - they are being used as power transformers aren't they?

Jason
  Reply With Quote
Old 14th January 2005, 10:16 AM   #9
diyAudio Member
 
Shoog's Avatar
 
Join Date: Aug 2002
Location: Eire
What I mean by restricting the frequency response is -

Torodial power transformers have a different sound to EI's, so they are effecting the power delivery at certain frequencies. The same question is relivent to filament transformers is it not?

Shoog
  Reply With Quote
Old 14th January 2005, 10:22 AM   #10
diyAudio Member
 
audiousername's Avatar
 
Join Date: Jul 2004
Location: Melbourne, Victoria
Shoog,

The EI type of transformer tends to have a narrower bandwidth than toroids, so more of the HF noise and other rubbish is attenuated. Is that what you mean?

Jason
  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
Filament Transformer dejanm Tubes / Valves 11 26th December 2013 03:21 AM
Filament transformer questions JoshK Tubes / Valves 1 12th March 2008 06:35 PM
Filament Transformer for 26 DHT korneluk Tubes / Valves 7 8th January 2008 07:25 PM
WTB: 6.3V Filament Transformer mrdon Swap Meet 1 20th March 2006 03:36 AM
Filament Transformer cantskienuf Tubes / Valves 1 24th June 2005 02:41 AM


New To Site? Need Help?

All times are GMT. The time now is 04:33 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