#1
I have notice that many mesa, especially the Mark series, have unadjustable fixed bias according to the schematic. In regarding to this, Randall smith (in that bias article attach to manuals) explain that it is better to just set a proper resistor and then forget it. Personally, that doesn't win me over, especially considering BillM's preference to make fixed bias adjustable (on blues Junior, but concept apply to other amps with such config).

So I am wondering: is it really okay to use seted fixed bias?
Ibanez SA-120 (ed.2006)
BluesJr 1996-B + cathode follower + texas Heat
Crate CPB150
Homemade 4 x 10 cab Bass closeback
Metal Muff
#2
it's ok if the tubes you use are tested to operate correctly in the fixed bias range, which is why Mesa tests their tubes and rebadge them with the Mesa logo. Any reputable tube dealer should be able to do the same thing for you if you tell them your amp.
"The fool doth think he is wise, but the wiseman knows himself to be a fool." - W.S.
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