6080 arcing on startup

tdubl07 · 1006

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Offline tdubl07

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on: April 14, 2014, 10:05:46 AM
Hey guys, I just got done building my Crack over the weekend, and it works fantastically. However on startup my 6080 arcs in tube,for a few seconds. It settles down and is fine afterwards but is this normal? It happened on Sat evening with my 990's plugged in and luckily didn't damage them. I now don't plug them in until it's thru arcing but just checking how common/uncommon this is.
Thanks
« Last Edit: April 14, 2014, 10:15:14 AM by tdubl07 »



Offline Paul Birkeland

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Reply #1 on: April 14, 2014, 11:14:56 AM
That's a somewhat uncommon occurrence. 

How did your voltage checks go?

The tube may be arcing due to a little residual gas, and this condition may go away with prolonged use.  I would try leaving the amp on overnight to see if you can cook the gas out.

-PB

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline tdubl07

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Reply #2 on: April 14, 2014, 11:22:36 AM
Voltage checks were all bang on. I've been listening all day at work and sounds great. Occasionaly however I will get a little ringing and if I tap the 6080 it goes away or gets louder and then goes away. I suspect it may be a bad tube. It just happens on startup and never again. Next startup it'll happen again. The saturday evening one was very scary as it was loud and also my phones were plugged in, and was quite the lightshow until I unplugged the amp. I ordered a 5998 already so I'm not too worried, I was just curious if it was uncommon as I've never had an amp with a power tube in it before. I'll probably order another 6080 as well since they're so cheap and readily available. These big tubes sure look cool!



Offline Grainger49

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Reply #3 on: April 14, 2014, 11:49:35 AM
There is an old Vaudeville routine.  A man says to his doctor, "Doc it hurts when I do this."  He is holding his arm above his head.

The doctor replies, "So don't do that."

I'm pretty sure 50% of the tubes out there will make a noise if you tap them.  So don't tap them.