Me tubes have turned blue (1 Viewer)

[Kermit McDermott]

Marshall JCM 800 4211. The tubes, or one of them is a glowing blue colour and the volume is waaaaay down . I'll have to get it fixed.

What's wrong with the fucker?

 

[Goodbye]

Perfect for playing the blues

 

[GO]

I thought this was a womens issue thread.Excuse me.

 

[D0njo]

I think tubes should be ok if they're glowing blue, there's something about it in the manual for my laney

 

[D0njo]

[FONT=verdana,arial,helvetica]Q: "My tubes are glowing blue. Should I worry?"[/FONT]
[FONT=verdana,arial,helvetica]A: No. Blue glow is perfectly normal. It's an artifact of operation of the tube. If the amp is otherwise working fine, relax and don't worry about it all.[/FONT]


[FONT=verdana,arial,helvetica]-http://www.kcanostubes.com/content/newsletter_details.asp?ArticleID=10
[/FONT]

 

[PaoloJM]

Usually a light blue glow is caused by gas in the vacuum. That's ok.

As far as the reduce volume is concerned I would replace the power valves to see if it solves the problem. Arcing power valves can often show a blue glow too. Ideally you'd want to re bias them as well.
If this doesn't solve the problem you need to take it to a tech to check it out fully. Reduced volume can be caused by a number of different things, thankfully on a Marshall valve amp all of them are fixable.