Broken GTEL84S (6BQ5) Tube - Works?

[riccihoms]

Hi, one of my Fender Blues Junior tubes seems to have broken down. It is one of the GTEL84S (6BQ5). The tip broke and the top is whitish.
I do not understand too much of electronics, but have a doubt regarding why does the amp still sounds, as if nothing had happened (seems like)
Is the 2nd bulb just a spare?
Is it safe to still use it or should I get a replacement ASAP?
thx, Ricardo

[Rob Mercure]

You've broken the tube and air has entered and the "getter" - a material within the tube designed to absorb some of the gasses left once the tube was evacuated - has now combined with all the gas it can and turned white. Stop using the amp until the tube can be replaced - and with this model you should probably replace them as a set. And don't waste your money buying fancy orange ink with gravy tubes - they are probably just silk screened sovwreks anyway. Get a good set of JJs and boogie on.

Rob

[Enzo]

What Rob said.


The second tube is not a spare, both tubes work to make the speaker move. But when one tube quits, there is still one left to try and cover it all. You would notice it more the louder you play in most cases.