What the heck is bias anyway?

Here's the classic simplified answer: Bias is to an amplifier what the engine idle speed adjustment is to a car. Set too low, there are performance issues. Set too high, and many cars and amplifiers also have performance issues, and additionally pay a price in efficiency and component life.

Now I'm admittedly somebody who has a penchant for verbose technical ramblings . . . but really, was it that difficult to answer the OP's question?

I think of the bias current in a tube amp as being similar to the fuel required to keep an engine idling. The engine must be running (idling) prior to applying throttle to accelerate (voltage). Maybe over simplified but works for my mechanical engineering brain.

I have a Cary SLI-80 that I must use a meter to set the bias current and it is very easy to do. I wouldn't freet it and it doesn't sound as if you are. Enjoy your new amp it is a beautiful piece to behold.

Chuck

Well, whatever the hell it is, it sounds really nice!

Thanks for the answers and food fight! :-)

Ecclectique - yes I got that one covered :-)

I had a Cary V12R before the CAD 120's. You need to use a meter, not just depend on the red led's. They run hot, but are a great amp. The led's show that the tubes are good. Happy listening.