Jump to content
Gibson Brands Forums

Blues Jr - loose tubes?

Recommended Posts

OK, I guess I should preface this question by saying that the sum total of my knowledge about the inner workings of tube amps could be written on the back of a postage stamp. About all I do know is that unqualified idiots like me shouldn't delve too deeply, because apparently there's a chance of ending up like one of Ol' Sparky's many customers...




I have a Fender Blues Jr. I noticed that the amp kept cutting out, and even I had sufficient acumen to check the tubes. Gingerly, (with a handkerchief around my fingers), I pushed the hot tubes. And sure enough, they pushed back into place and the amp was back to normal.


But this is a recurring problem. Whenever I take the amp to a rehearsal or a gig, the tubes work loose. I'm never rough with the amp - I transport it to gigs inside my Jeep, wedged in the space between the back of the driver's seat and the back seat.


The tubes in question are the ones on the left, supported by some sort of little metal spring-tensioned device (I assume that these have to be the output tubes?)






To cut a long story short. I love my amp, but it's a bit of a pain to have to be constantly checking the tubes. This never happened with the last tube amp I had (a Laney VC30).


Is this a Blues Jr problem, or is there something I can do to fix it?


Thanks for your help / advice.



Link to comment
Share on other sites

Yep. Those taller ones under the bracket are the EL84 power tubes. You'll need to pull 'em and get inside the amp so you can get at it with a steel poker or something to retention the tube socket's pin receivers. They just need a little tweaking is all.



Link to comment
Share on other sites

All good advice, but be careful. it takes just a little tweek, if you push too hard you might crack the base or crush the metal socket.


The price of copper has caused many manufactures to use thin spring steel. and they, at best, may only have a thin copper or gold plating.


I worked in the automated electronics industry for several years. I was in one of Fender's assembly plants in California in the mid '90's. I could not believe the crappy quality of the parts they were using. I had a super reverb deluxe in the sixties, so I know what they used to use.


Take your time, use just a slight nudge on the outside of each pin socket (you can see the small gap where the metal socket was rolled) You only need to close that gap a tiny bit.


Now you also need to check the tubes after every move and also check the screws that hold the chassis in the case and the back cover, any looseness there can cause the tubes to vibrate.

Link to comment
Share on other sites


This topic is now archived and is closed to further replies.

  • Create New...