Hm, which order to replace 2 out of 4 tubes? - 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 10th June 2011, 02:23 AM   #1
hugz is offline hugz  Australia
diyAudio Member
 
Join Date: Jan 2005
Location: Brisbane, Australia
Default Hm, which order to replace 2 out of 4 tubes?

I have a 2 channel preamp with 2x 6sn7 per channel (4 total). Presumably push/pull?

Unfortunately 2 of the tubes (1 per channel) are horribly microphonic so I'm going to buy 2 new tubes to replace. I'll buy a fancy brand, so I can only afford 2 at a time

For sake of the example, we'll assumre I've thrown out the bad ones, and the remaining tubes are "cheap" but the new ones will be "fancy"

Which setup would be more sensible:
  1. Have one "fancy" and one "cheap" tube per channel
  2. Have 2 "cheap" ones in one channel and 2 "good" ones in the other channel)

The essence of the question is really "is it a waste of a good tube to put it in the same channel (presumably push/pull) with a cheaper tube?
  Reply With Quote
Old 10th June 2011, 03:23 AM   #2
tomchr is offline tomchr  United States
diyAudio Member
 
tomchr's Avatar
 
Join Date: Feb 2009
Location: Greater Seattle Area
I would install them such that you have two identical channels in your amp.
  Reply With Quote
Old 10th June 2011, 03:30 AM   #3
diyAudio Member
 
Michael Koster's Avatar
 
Join Date: Jan 2008
Location: Eureka, CA
Did you try swapping the 2 tubes within each channel to verify that it's not just the first gain stage that's sensitive?
  Reply With Quote
Old 10th June 2011, 03:45 AM   #4
hugz is offline hugz  Australia
diyAudio Member
 
Join Date: Jan 2005
Location: Brisbane, Australia
Quote:
Originally Posted by Michael Koster View Post
Did you try swapping the 2 tubes within each channel to verify that it's not just the first gain stage that's sensitive?
Both channels were noisy so I moved both of the bad tubes to the same channel. now one channel is noisy and the other is quiet.

Did you mean though to just sap the positioning of the tubes within each separate channel?

Eg the tubes are as follows

..left....right

..1.........2
..3.........4


1 & 2 were both /microphonic, so I moved tube 2 to where tube 3 was. This gave me a noisy left ch and clean right ch

You're suggesting swapping 1 & 3, and 2 & 4 ?

What would I be looking out for if I did this?

Thanks
  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
Tamura HM-1 fxsound Tubes / Valves 2 20th July 2009 07:42 AM
the audax hm 170c0 Larin Multi-Way 16 27th June 2008 08:34 AM
7868 tubes - replace with 6L6's? PRNDL Tubes / Valves 6 29th November 2007 07:11 PM


New To Site? Need Help?

All times are GMT. The time now is 07:59 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