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Marshall JTM60


 :
12/10/2000 11:23 PM
Dan J
Marshall JTM60
Help !  
 
 
 
I have a JTM 60 with low volume out. The tubes  
 
were recently replaced, but didn't seem to help.  
 
I don't know if the bias was set when the tubes  
 
were replaced. I checked the bias upon turn on  
 
and the bias read about 40ma (EL-34's)after the  
 
amp warmed up about 5 mins. the bias read about  
 
120ma. on one side and about 80ma on the other.  
 
I was able to adjust the bias down to @ 40ma again  
 
on both sides, but did the tubes get cooked ???  
 
The volume is still low and distorted, even on the  
 
clean channel.
 

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