Twists per inch on filament wiring? - Page 2 - 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 22nd December 2003, 04:27 PM   #11
diyAudio Member
 
Join Date: Dec 2001
Location: Eindhoven
Default Re: The more the merrier

Quote:
Originally posted by EC8010
As Sch3mat1c says, it's all about having the same capacitance from each heater wire to a given audio point. An infinite number of twists per inch would guarantee equal capacitances, and provided that the heater wiring was perfectly centre-tapped to earth, would produce zero hum. Since more twists per inch doesn't cost money, I use as many as I can. Solid core wire is much easier to twist tightly. Push it tight into the corners of the chassis, and bring it up to the valve at the last moment.

If capacitive coupling is inducing the hum, I'd suggest a screen, much easier to apply

Mostly it is inductive coupling

Ciao
__________________
Guido Tent
www.Tentlabs.com
  Reply With Quote
Old 22nd December 2003, 05:15 PM   #12
EC8010 is offline EC8010  United Kingdom
diyAudio Moderator Emeritus
 
EC8010's Avatar
 
Join Date: Jan 2003
Location: Near London. UK
It's both, but you don't need much of a twist to cancel the magnetic field. Screening heater wiring is possible, but tends to be fiddly. To keep this in perspective, the classic valve manufacturers managed to make RIAA pre-amplifiers with tolerable hum using AC on their heaters.
__________________
The loudspeaker: The only commercial Hi-Fi item where a disproportionate part of the budget isn't spent on the box. And the one where it would make a difference...
  Reply With Quote
Old 22nd December 2003, 05:45 PM   #13
diyAudio Member
 
Join Date: Dec 2001
Location: Eindhoven
Quote:
Originally posted by EC8010
It's both, but you don't need much of a twist to cancel the magnetic field. Screening heater wiring is possible, but tends to be fiddly. To keep this in perspective, the classic valve manufacturers managed to make RIAA pre-amplifiers with tolerable hum using AC on their heaters.

Hi EC8010,

The dominant coupling mechanism depends on both source and receiving impedance.

Perspective is correct, but to make it a little more quiet.....

Once had capacitive coupling from anodes of rectifier tube. Rotated that until coupling was balanced :-)
__________________
Guido Tent
www.Tentlabs.com
  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 wiring question Magnetmaz Tubes / Valves 26 18th September 2010 05:37 AM
Filament Wiring - Shielded vs. Twisted? k9swc Tubes / Valves 21 27th May 2009 07:12 PM
2 inch Peerless vs 2 inch HiVi Research richie00boy Multi-Way 18 5th December 2007 07:31 PM
Parallel vs. series filament supply - or another filament idea engels Tubes / Valves 11 13th May 2007 01:06 PM
Passive Radiator system with 2x10 inch and 1x15 inch Lach O'Sullivan Multi-Way 3 13th September 2003 03:29 PM


New To Site? Need Help?

All times are GMT. The time now is 07:52 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