Only three power tubes are blue

[EirikBrandal]

Ok,

all of my power tubes are glowing in red, but only three of them are glowing blue. And the one that's glowing blue is not as hot as the three others. Is it supposed to be like that?

 

[Mulemasta]

I had the same problem with my IIC, there was a blown cap inside, tech fixed it easily enough. The amp had a bad hum, and sounded like crap. Sounds better than ever now.

 

[EirikBrandal]

but my mark IV sounds pretty good lol. At least not like crap

 

[MrMarkIII]

Blue is normal.
Is the cooler tube the one closest to the fan?

 

[EirikBrandal]

I know blue is normal, but there's only three blue. And it's impossible to say that one is closer to the fan than another, because they're all in line.

But I touched them all, and the three blue ones were hot as youknowwhat, while the last one was like the amp was on standby

 

[disassembled]

That is a sign of bad tube or maybe a problem inside the amp.

Greg

 

[EirikBrandal]

It's not a bad tube, cause I have already swapped it a few times

 

[MrMarkIII]

"Not-blue" is also nornal.

 

[EirikBrandal]

sure, but what about the heat, and the three others?

 

[Shep]

hey dude. Switch around the pair of the one that is glowing cooler. And if the new tube in that space is doing the same thing then it's your amp. It will most likely be something to do with your b + voltage supply for that tube.but take it to a tech if you don't know what your doing.