Caliber50+ bias problem

Hello everybody !
I have a cal. 50+ combo (6L6 version), which sounds terrible. Sounds scratchy and edged, the sound does not hold, I tested the voltages, and have bias voltage of -80 volts on both 6L6 ! That would have to be according to plan -47 V.
Unfortunately, it seems that the schematics that I found do not match with my combo. According to the schematic after the transformer (red cable) comes a diode (1N6004) to block positive voltage, then a 47k resistor and then 2 resistors tied together 68K and 82K . ..... . But I can not find the 47k resistor here, the diode goes directly to the tied pair.. And after them there is a 33k resistor... that i can not find the shematics. The preamp (send as output) sounds perfect. The 6L6 tubes tested in a fender 75 head,are sounding also good. Does anyone have a schematic for this version, or is this problem known?

Maybe I 'm taken a step forward . I mesured the tied resistors 82K and 62K : instead 82K only 48K , and instead of 68K only 58K . I changed the resistors , and the bias is ok again ... 47V , and it sounds healthy again . But now is a noise as that grows with the gain , but rushes suddenly no longer when the gain is turned fully . And a hum is noticeable , it is buzzing even much stronger if the graphic eq 80 and 240 Hz regulator are fully up or down . And in the EQ is OFF !!! The humming get really loud, if I set the two slide controls (80Hz and 240Hz ) to the extrem +db and -db. And again; the EQ is not switched on ! Is this still the same problem or is it another ?