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Silver Jubilee 2555 bias issue

Posted: Thu Nov 19, 2015 6:16 pm
by Mxzx
I pulled a properly biased set of Groove Tube GT34LS's and replaced with a quad of JJ EL34's.

The highest I can get the bias is now 18ma's. I have looked at the 2555 schematic and I am still not sure which resistor is the bias range one. I thought it might be R23 but my amp doesn't have anything there.

This is an original Jubilee if that matters.


Any ideas?
Thanks