Tube pulling question

[toejam]

I know on amps with at least 4 power tubes that you can pull a pair of them out to run at lower power and volume. Can you pull tubes out of an amp that runs on only 2 or 3 power tubes to begin with and have it run sufficiently or is it not good?

[Shawn Lutz]

Re: Tube pulling question

normally no. I'm no amp expert by any means, I just use them [img]/images/graemlins/smile.gif[/img] but tubes in most amps work in push-pull pairs.

I have 2 6550's in my 4 tube 2203 and the volume level reduction isn't that noticable if at all from going from 100 watts to 50

[charvelguy]

Re: Tube pulling question

yellow jackets, or Groove Tubes makes the 928 PR, I believe Ruby had a converter as well.

You alter the plate voltage I believe when you pull a tube. I am not an amp guru either, but on a 100watt, you are pulling out one stage of the output (outer two or inner two) and it still should be rebiased.

[toejam]

Re: Tube pulling question

Thanks, guys!

[charvelguy]

Re: Tube pulling question

If I recall, you kinda liked the el84 route. Besides the obvious difference in tube shape and size.. convertors (and the change to el84) will change the tonal character 'slightly', not a bad thing..you are just going from push/pull A/B and converting to class A, class A amps have differing characteristics. A 50 watt marshall will tend to sound more like a vox or have character of a vox tube amp.