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300B tube death question........


Has anyone experienced the death of their 300b tube? What happened.....Exploded? Imploded? Awesome fireworks display? I'm just preparing myself for when it happens.

Also, the 300b tubes in my amp is underbiased and it won't reach optimum recommended voltage settings (volt meter should read 700ma but tube is at 450ma). The amps have manual bias adjustments only.

So far nothing has happened and the sound is fine. Should I replace them now or wait until they die? (see above question).

Amps: ASL monoblocks SET amps - (2) 300b per channel
Tubes: Valve Art 300B 98C

Thank you for sharing.
dogpile

Showing 2 responses by dogpile

dogpile OP
118 posts
 

SWAMPWALKER - Even when the pots are turned to maximum, bias will not reach recommended 700. I know it's the tubes because I tried different positions and it followed with the same results.

HERMAN - Three out of the four can bias to 700 no problem. The one at 450 is the same brand and was purchased new.

MARAKANETZ - Problem is just with the one tube. I know it's not the amps.

How will I know when a 300B tube is on it's last legs?

Enen though the music is still there (little degradation sonically), should I continue using this tube or replace it immediately?

Thanks again.
dogpile OP
118 posts
 
I think I'll just replace the one tube since the other three are still low hours. The place where I initially bought them cannot take returns which SUCKS! Goes to show, even tubes advertised as NEW can have low emissions. I'll search for a different supplier, perhaps Conus in Canada.

Thanks guys!
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