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Biasing for new tube

I'm new to the tube world so I apologize if this is a no-brainer question for the experts. I am replacing one tube in a VTL MB 185 that arced on me. Do I need to check bias after the new tube is installed -- the VTL manual tells me to do so when I install all new tubes, but it's not clear as to the procedure when replacing a single tube. I'm getting the replacement tube from VTL. Any help will be greatly appreciated.
vtl
thorman
1,262 posts
 
I always turn down the bias on the old tubes before I put in the new tubes.Your old tubes do get tired and need more of a push ,so when you put in your new ones they shouldn't need as high a bias....This works for me...
mmaudio
27 posts
 
Jax2,

Forgive me, but as a newbie at tube biasing myself, why do you recommend removing the interconnects before biasing?

mmaudio
jax2
3,031 posts
 
Mmaudio - As I understand it, any current/signal/input at the terminals may alter the readings. Some folks recommend simply turning the volume all the way down on the preamp, or shutting it off. I've was taught that the safest way was to simply remove the connection altogether.
vtl OP
19 posts
 
Thanks for all of the help; my first attempt at checking bias and re-setting bias were successful -- and no injuries were sustained!
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