Go Back   Home > Forums > >
Home Forums Rules Articles diyAudio Store Blogs Gallery Wiki 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

Which components should be matched?
Which components should be matched?
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 9th April 2006, 08:10 PM   #1
boneshaker is offline boneshaker  Europe
diyAudio Member
Join Date: Apr 2005
Location: Mainz
Default Which components should be matched?


I am going to build my first audio amp (but I built several guitar amps): the WAD KEL84 (http://www.world-designs.co.uk/acatalog/kel84.pdf). It is a simple Push-Pull EL84 amp.

Which components should be matched in such an amp (in a guitar amp this is not necessary).

I am asking because there is a guy selling stereo volume pots that are selected for minimum tolerance (so that the 2 channels are identical as much as possible to one another).

Does this make sense? (Especially since the tubes used in the 2 channels will vary anyway.)

Are there other critical componentes that should be matched, too, to make the two stereo channels of the amp as identical as possible?

(I was going to use resistors with 1% tolerance, BTW.)

  Reply With Quote
Old 10th April 2006, 03:38 AM   #2
kevinkr is offline kevinkr  United States
diyAudio Moderator
kevinkr's Avatar
Join Date: Sep 2004
Location: Boston, Massachusetts
Which components should be matched?
Actually this does make a lot of sense as tracking between sections in stereo pots is often as bad as 3dB section to section. This results in possible fixed level mismatch between the channels over most of the control's range as well as a possible variation in mismatch between the channels as you change the setting of the volume pot.

Triodes have pretty consistent mu, and hence voltage gain, provided that the passive component values are reasonably well matched from channel to channel.

1% resistors are fine, in most instances 5% resistors are ok too if you wish to use vintage allen bradley carbon comps for example.
"To argue with a person who has renounced the use of reason is like administering medicine to the dead." - Thomas Paine
  Reply With Quote


Which components should be matched?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

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Matched IRF FET's Tarasque Swap Meet 219 27th February 2011 11:58 PM
Matched tubes or not matched hilbert_mostert Tubes / Valves 29 27th March 2009 11:13 PM
F4 matched FET's Tarasque Group Buys 205 14th October 2008 03:59 PM
Impedance matched amp Charles BL Pass Labs 9 19th November 2002 03:22 AM

New To Site? Need Help?

All times are GMT. The time now is 11:29 PM.

Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 16.67%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
Copyright ©1999-2017 diyAudio